In the year 1947, the people of Shinjuku are down on their luck. With little money to buy food or necessities, some resort to gambling in order to survive. Traveling Tetsuya chooses to spend his time at Mahjong parlors where he is wiping the floor clean with his adversaries. However, Tetsuya meets the intensely-skilled Boushu-san, this is when he realizes that his skills are still lacking.

Note: Won the 2000 Kodansha Manga Award for shounen.

From MangaHelpers:

History classes have never interested Saburo. He never saw the point of learning something that happened in the past, let alone a few hundred years ago. But when he falls off a wall, he travels through a wormhole and ends up in 16th century ancient Japan. He meets a very young Oda Nobunaga, one of the most influential figures in Japanese history, who turns out to be identical in appearance as Saburo. The real Nobunaga, sick of the castle life and wanting to travel, orders Saburo to take his place. Without knowing how to get back to his time, Saburo tries to make sure history isn’t rewritten for the infamous Oda Nobunaga. [vyc]

Won the 57th Shogakukan Manga Award for shounen.

In recent years, Japan has become the shining light of Asia, with its noteworthy achievements in the fields of Science and Technology, Medicine and the like.
But while there are a great number of rich and successful Japanese people, there are even more who're engaged in a furious struggle simply to earn their day-to-day living expenses -- all the while battling dangerous and money-consuming addictions such as gambling and alcoholism. What will these people do when they require the cash to feed the never-ending desires that are part and parcel of being human? How miserable and dangerous might their lives become if they fall into traps set by black market money-lenders to ensnare just such weak-willed individuals?

Note: Won the 56th Shogakukan Manga Award for general manga in 2011.

Before the Pirate King was executed, he dared the many pirates of the world to seek out the fortune that he left behind in one piece.
As a child, Monkey D. Luffy dreamed of becoming the King of the Pirates. But his life changed when he accidentally gained the power to stretch like rubber...at the cost of never being able to swim again! Now Luffy, with the help of a motley collection of nakama, is setting off in search of "One Piece", said to be the greatest treasure in the world.

Note: The best-selling series in manga history.

Was a finalist for the Tezuka Osamu Cultural Prize from 2000 to 2002. The German translation of Vol 44 won the Sondermann audience award at the Frankfurt Book Fair Comics Centre in 2005.
Won the 41st Japan Cartoonists Association Award Grand Prize alongside Neko Darake in 2012.

The story begins with Japan's elimination from the 2018 FIFA World Cup, which prompts the Japanese Football Union to start a programme scouting high school players who will begin training in preparation for the 2022 Cup. Isagi Youichi, a forward, receives an invitation to this programme soon after his team loses the chance to go to Nationals because he passed to his less-skilled teammate —who missed— without trying to make the game-changing goal by himself.

Their coach will be Ego Jinpachi, who intends to “destroy Japanese loser football” by introducing a radical new training regimen: isolate 300 young strikers in a prison-like institution called “Blue Lock” and put them through rigorous training aimed at creating “the world's greatest egotist striker.”

Note: Won the 45th Kodansha Manga Award in the shounen category in 2021.

The master spy codenamed has spent his days on undercover missions, all for the dream of a better world. But one day, he receives a particularly difficult new order from command. For his mission, he must form a temporary family and start a new life?! A Spy/Action/Comedy about a one-of-a-kind family!

Won the Tsugi ni Kuru Manga Award 2019 in the web manga category.

The story is about Mutsu Tsukumo, a young and normal looking youth who challenges great foes to prove that his style of fighting is the best in the world. His Ryuha, or fighting style is called Mutsu Enmei Ryu. A style that is said to have never lost in its 1000 year history. Tsukumo not yet a perfect fighter also increases his strength as the story progresses.

Won the 14th Kodansha Manga Award for shounen in 1990.

Inaho Jr. High's Boys Ping Pong Club has only 6 members, the club minimum. Takeda is your average nice guy. Kinoshita is good looking and popular with girls. Unfortunately, the rest are branded as losers. Tanabe is too foreign, while Tanaka is petite and perverse. Maena and Izawa are truly deviant, and their crazed antics have earned the team some powerful enemies. In spite of their differences, the team needs to work together to retain their practice room and club status.

Note: Won the Kodansha Manga Award for general manga in 1996.

From Exertus Scans:
Millions of years have passed since the times of legends, when the worlds of man and gods were still the same. In these times it was the desires of man that moved the world. It is the era of the 500 year war: The warring states period. Kingdom is the story of a young boy named Shin who grew into a great general and all the trials and bloodshed that lead him there.

Note: Kingdom won the grand prize for the Tezuka Osamu Cultural Prize in 2013.
The manga also earned a Guinness World Record on December 12, 2012 for Manga written by the most people. The record was due to its "Social Kingdom" campaign in which fans and other artists were given the task of redrawing the entire 26th volume.

In this new action-comedy, everything about a young man named Saitama screams "AVERAGE," from his lifeless expression, to his bald head, to his unimpressive physique. However, this average-looking fellow doesn't have your average problem... He's actually a superhero that's looking for tough opponents! The problem is, every time he finds a promising candidate he beats the snot out of them in one punch. Can Saitama finally find an evil villain strong enough to challenge him? Follow Saitama through his hilarious romps as he searches for new bad guys to challenge!

Note: Nominated for the 7th annual Manga Taishou Award in 2014. Won the 2017 Sugoi Japan Award. The manga also was nominated for an Eisner Award in 2015 and a Harvey Award in 2016.

In the year 200X, a Japanese fleet consisting of 3 vessels leave on a mission to South America. After encountering a storm, the ship JDS Mirai find itself without its escorts and in the year 1942, traveling towards the island of Midway to face the American fleet in one of largest battles in naval history. The crew of the Mirai must decide whether or not to change the course of history by involving itself in WWII.

Won the Kodansha Manga Award for general manga in 2002.

There's a new hero in town and he's got a bad attitude and a chainsaw dog demon! A dangerous combo.

Note: In 2021, the manga won the 66th Shogakukan Manga Award in the shounen category.

The story revolves around the lives of two rough-and-tumble high-school friends Kato Hiroshi and Nakama Toru, who seemed to make a habit of getting into trouble and starting up fights. In keeping with the spirit of the manga, Toru and Hiroshi sport slicked back 50's style perms and adopted exaggerated swaggers that made them comical and yet also oddly cool. The drama also features an assortment of outlandish characters who sport even weirder fashions and hairdos. To describe the action in this drama, think Fight Club meets The Breakfast Club.

Won the 12th Kodansha Manga Award for general manga in 1988 (shared with Bonobono).

Kato Kotono, a historian, presents a fantastic tale woven of intricate historical details set in a time of war.

Mahmut is a young Pasha serving on the council of the Türkiye Stratocracy. The clouds of war are gathering over his country as the threat of the aggressive Empire looms large. With Türkiye's council split between the warmongers and the pacifists, Mahmut begins his quest to keep the peace at any cost. As he finds himself drawn deeper and deeper in the politics of the ancient world, new enemies and allies surface. Who will prevail? What will Mahmut do if war proves to be inevitable?

Volume 4 includes an oneshot: Anastasia no Shinei Taichou.

Won the 41st Kodansha Manga Award for Shounen in 2017.

Makunochi Ippo is an ordinary high school student in Japan. Since he spends most of his time away from school helping his mother run the family business, he doesn't get to enjoy his younger years like most teenagers. Always a target for bullying at school, Ippo's life is one of hardship. One of these after-school bullying sessions turns Ippo's life around for the better, as he is saved by a boxer named Takamura. He decides to follow in Takamura's footsteps and train to become a boxer, giving his life direction and purpose. Ippo's path to perfecting his pugilistic prowess is just beginning.

Note: Won the 15th Kodansha Manga Award for Best Shounen Manga in 1991.

Hyakkaou Private Academy. An institution for the privileged with a very peculiar curriculum. You see, when you're the sons and daughters of the wealthiest of the wealthy, it's not athletic prowess or book smarts that keep you ahead. It's reading your opponent, the art of the deal. What better way to hone those skills than with a rigorous curriculum of gambling?
At Hyakkaou Private Academy, the winners live like kings, and the losers are put through the wringer. But when Yumeko Jabami enrolls, she's gonna teach these kids what a high roller really looks like!

Note: Placed 3rd in the DaVinchi x NicoNico Tsugi 2016 Manga Awards.

Sasaki, an overworked salaryman, goes through an average stressful day just for a single light at the end of the tunnel: Yamada, the always-cheerful clerk at his favorite convenience store.

One day, Sasaki takes an extra amount of time at a company meeting, and by the time he gets to the convenience store Yamada has already clocked out. However, as he leaves, he notices a young woman with piercings smoking behind the store?

Note: The manga won the 2022 Next Manga Award in the web manga category.

Shinichi Kudo is a high-school student who, by using observation and deduction, is good at solving mysteries. While investigating one, he is caught by the criminals that he was watching and forced to take an experimental drug. Leaving him for dead, the criminals disappear. Instead of killing him, however, the drug turns Shinichi into a little kid.
To preserve the illusion of his 'disappearance,' Shinichi adopts a new name based on his favorite author (Arthur Conan Doyle) and becomes Conan Edogawa. Ran, his (actually Shinichi's) childhood friend takes this little boy under her wing and brings him to her home.
Conan now lives at a detective agency run by Ran's father, but his mind is as keen as ever and he continues to solve mysteries... always allowing Ran's father to take all the credit.
As far as everyone's concerned, Conan is just a little kid anyway... even to Ran. This is *extremely* frustrating to Conan since nobody will listen to a 'little boy.' Despite this, Conan has a mission... to find the criminals who did this to him and get the antidote to that drug.

Note: Won the 46th Shogakukan Manga Award in the shōnen category in 2001.

In his second to last year of high school, the dispassionate but studious, Yataro Yaguchi finally finds a calling in art. With no prior art experience, he decides to work towards applying to an art university. A decision with potentially disastrous results.

Iwakura Mitsumi always had big dreams, of leaving her small town, advancing to the top tier university, and then contributing to the country before retiring back to her home town. So focused is she to her goal that she is oblivious to all the other ways she comes up short, much to the chagrin and concern of her friends and family. Can a naive country girl make it in Tokyo?

Note: In 2023, this manga won the 47th Kodansha Manga Award in the general category.