Hinomaru Sumo (Japanese: 火ノ丸相撲, Hepburn: Hinomaru Zumō) is a Japanese sumo manga series written and illustrated by Kawada [ja]. It was serialized in Shueisha's shōnen manga magazine Weekly Shōnen Jump from May 2014 to July 2019, with its chapters collected into 28 tankōbon volumes by Shueisha. A 24-episode anime television series adaptation produced by Gonzo aired from October 2018 to March 2019.

On his first day of high school, sumo practitioner Hinomaru Ushio joins Odachi High's sumo club. Despite his short stature (professional sumo has a height requirement of 167 centimeters (5.5 feet)), Hinomaru aims to become the best in high school to force the professional sumo association to let him compete, and then reach the sport's highest rank of yokozuna. However, the club's captain and only other member, third year student Shinya Ozeki, informs him that delinquents have taken over their dojo. Hinomaru challenges their leader and "strongest" student at the school, Yuma Gojo, to a fight to take back the dojo, and beats him with one hit. Humbled, Yuma also joins the sumo club after being dragged to a practice match by Hinomaru and seeing how strong the wrestlers are. They compete in a local three-man team tournament, but are knocked out by Ishigami High School. In order to avoid having the club shut down, they recruit two more members during the two-day cultural festival; the national wrestling champion Chihiro Kunisaki, and the small, unathletic Kei Mitsuhashi.

The members of Odachi High's sumo club then enter the Kantō newcomer tournament, which is fought one-on-one, where Chihiro, Yuma and Hinomaru are all defeated by the return of the prodigy Sōsuke Kuze. Hinomaru's childhood friend Kirihito Tsuji enters Odachi High and becomes the coach of the sumo club. Tsuji devises training regimens for each member, including having Hinomaru train with professionals at Shibakiyama stable, to get them ready for the Chiba preliminaries of the Inter High Tournament. At the preliminaries, Odachi High defeats Ishigami High in the team finals earning a spot at the nationals, while Hinomaru wins the individual tournament. Shibakiyama invites Odachi High to Nagoya to train with professionals, where Hinomaru gets special training with sekitori and former yokozuna Shunkai Tokio. On the first day of the national Inter High Tournament at Ryōgoku Kokugikan, Hinomaru is eliminated from the individual competition by reigning champion Shido Tennoji and injures his arm. With Hinomaru out for the rest of the day, Odachi High advances in the first two rounds of the team competition without him. On the third and final day, Odachi High and Hinomaru defeat Tottori Hakurou High and Tennoji in the semifinals, before defeating Eiga University High and Kuze in the finals to become the national champions.

Three and a half years later, Hinomaru is returning to the top makuuchi division of professional sumo after having suffered a serious injury to his right arm two years earlier. During the July tournament in Nagoya, Hinomaru defeats Tsuji before Mongolian yokozuna Jin'o, who has reigned at the top of the sport for the last decade, wins his 44th championship and announces he will retire if he wins the next one due to a lack of competition. This lights a fire within the young Japanese wrestlers and they organize a training camp together in Gifu Prefecture in order to defeat him. After Hinomaru loses on the second and third days of the September tournament, including once to Jin'o, the old Odachi High sumo club reunites to help him strategize and stays to support him. On national television after defeating ōzeki Kinkaizan, Hinomaru proposes that he and Reina marry after the tournament. Hinomaru goes undefeated for the rest of the tournament and defeats Ozeki on the 15th and final day. Although Jin'o is initially ruled the winner of his final day bout with Kuze, Tennoji calls a mono-ii and the decision is overturned into a win for Kuze. This forces the need for a playoff between four wrestlers with 13–2 records. Jin'o defeats his stablemate Akihira Kano, and Hinomaru defeats his stablemate Norihiro Saenoyama. Hinomaru then defeats yokozuna Jin'o to win the September tournament. In the epilogue six months later, Hinomaru and Reina have gotten married and he is still competing in the top division.

After having had several works published in the Kodansha magazines Morning and Monthly Morning Two, Kawada [ja] submitted a work to Shueisha for their Tezuka Award. It won an honorable mention and Hitoshi Koike was assigned as his editor. Koike suggested he continue to write seinen manga for a magazine such as Weekly Young Jump, but Kawada strongly desired to try his hand at shōnen manga. The idea for Hinomaru Sumo came from Kawada's own interest in sumo. Although he had always liked it, he really got hooked on the sport when Asashōryū was in his prime, which was around the time he became a professional manga artist. Kawada said that this was also when sumo's popularity was declining, so he wanted to spread the passion of sumo and therefore wanted to do it in the popular magazine Weekly Shōnen Jump. The story he initially pitched for the manga had two protagonists; one who loves sumo like Hinomaru Ushio, and another that ended up becoming the prototype for Yuma Gojo. But Koike felt the story did not make much sense because it had too much content and too many characters. So he told Kawada, "I simply want a character who shows the greatness of sumo from an outsider's point of view." The one-shot was published in the Spring 2013 issue of Shōnen Jump Next!.

Koike suggested that, despite sumo being well-known, the young readers of Weekly Shōnen Jump at the time probably did not have a good image of the sport; this is expressed in the first chapter of the manga where a character comments that sumo is just "two fat guys hugging naked". But the editor said, "Sumo is a sport with a long history and tradition, so if you can get over the initial prejudice of readers, it is a treasure trove of attractive material for manga." He explained that he and Kawada tried their best to overturn that perception by conveying the feelings of the athletes and fans who devote their lives to the sport. He cited conveying why the good-looking character Mizuki Sada competes in sumo as one of these attempts to gain readers' interest. From the beginning of the series, the artist and editor were aware of the necessity of characters having special moves, but Kawada said he was always conscious of depicting it as fiction while maintaining the realism.

Written and illustrated by Kawada [ja], Hinomaru Sumo began serialization in Weekly Shōnen Jump on May 26, 2014. A crossover chapter between the series and Tadatoshi Fujimaki's Kuroko's Basketball, with a script written by Ichirō Takahashi, was published in the magazine on November 9, 2015. Kawada was formerly an assistant to Fujimaki on Kuroko's Basketball. Hinomaru Sumo is split into two parts; "Part 1: Student Sumo Arc" finished with chapter 159 on September 4, 2017, while "Part 2: Professional Sumo Arc" began in the following issue. The 250th and final chapter of the series was published on July 22, 2019, with an epilogue published on October 4, 2019, on the Shōnen Jump+ platform. Shueisha compiled its individual chapters into twenty-eight tankōbon volumes between September 2014 and December 2019. They began to simulpublish the series in English on the website and app Manga Plus in January 2019.

The first chapter of Hinomaru Sumo received a four episode "vomic" adaptation for the television show Vomic TV, and aired on Animax between February 4 and 28, 2015. The program adds voice actors, sound effects and background music to the manga pages.