Yoshizawa began his acting career after winning the "Right-on" award at
Amuse National Audition 2009 THE PUSH! Man held by talent agency
Amuse. He competed against 31,514 other applicants. Yoshizawa's mother was the one who encouraged him to join the audition. He was motivated because of the 1 million yen prize money but then felt disappointed when he only got a special award without monetary reward. A month after the audition announcement ceremony, he was contacted by a manager and agreed to sign with Amuse. In the beginning of 2011, Yoshizawa made his television drama debut in
Sign with other Amuse actors like
Dori Sakurada and Takuya Uehara. In the second half of that year, he starred in NHK youth drama
Kingyo Club. He went on to portray
Ryusei Sakuta in
Kamen Rider Fourze, In 2017, he portrayed the role of Shinsengumi 1st Division Captain Okita Sougo in
the 2017 live-action film of the popular manga series
Gintama, and reprised the role in the sequel,
Gintama 2, in 2018. In 2018 alone, he actively participated in acting, appearing in 8 movies, 2 dramas, and 1 play. Among them, ''
River's Edge'', a film of the same name based on
Kyoko Okazaki's manga, was submitted to the Panorama section of the 68th Berlin International Film Festival, and Yoshizawa appeared at an international film festival for the first time with director
Isao Yukisada and actress
Fumi Nikaido. In addition, for this work, he won the Best New Actor Award at the 10th Tama Film Festival, the Best New Actor Award at the 40th Yokohama Film Festival, and the Best New Actor Award at the 42nd Japan Academy Awards. In NHK's 100th serial morning drama,
Natsuzora which aired from April 2019, Yoshizawa played the role of Yamada Tenyo, a character based on the real-life painter
Kanda Nissho, a childhood friend of the protagonist Natsu. He was selected through an audition of over 2,500 people. Since the airing of the 23rd week, in which his character Tenyo last appears, 'Tenyo-kun' has appeared in real-time trends on Twitter, to the point where people are suffering from 'Tenyo-kun aftereffects'. His performance in Natsuzora and movie Kingdom earned him the 2020 Elan d'or Awards for Rookie of the Year. In September 2019, it was announced that Yoshizawa had been chosen to portray
Shibusawa Eiichi, the lead character of NHK's 60th
taiga drama,
Reach Beyond the Blue Sky which is scheduled to air from February until December 2021. Yoshizawa is the first Heisei-born actor to play the lead role in a taiga drama, he was selected through an offer from NHK and it was said that there were many recommendations from the production team who worked with him on
Natsuzora. Yoshizawa also attempted voice acting for the first time, performing two roles in his first attempt at Super Peace Busters' new work,
Her Blue Sky. With this work, Yoshizawa attended the Sitges Film Festival, where the work was submitted, along with director
Tatsuyuki Nagai and actress
Riho Yoshioka. He also voiced original character, Rody Soul, for third movie version of the animation series
My Hero Academia, which was released on August 6, 2021. Yoshizawa alongside actress
Aoi Miyazaki starred in a Netflix mystery & romance comedy movie,
In Love and Deep Water, that premiered in November 2023 which
Yuji Sakamoto was the screenwriter. From October 2022, Yoshizawa took on his first lead role in
Getsuku (Golden Time) drama,
PICU: Pediatric Intensive Care Unit, playing the role of Takeshiro Shikota. It is also his first doctor character since his debut and the average viewer rating of the drama was 8.5%. He reprised his role for the special drama and spin-off of
PICU: Pediatric Intensive Care Unit, which aired in April 2024. Yoshizawa stars in
Lee Sang-il's 2025 film
Kokuho (). He plays Kikuo Tachibana, a yakuza's son who performs as a woman in kabuki. The film is based on the novel by
Shuichi Yoshida and tells the story of two men from different backgrounds who become rivals in kabuki, one a yakuza's son and the other a kabuki heir, in postwar Japan.
Kokuho has been officially selected for the 57th Directors' Fortnight at the 78th Cannes Film Festival. Following
Natsuzora, Yoshizawa was announced to join another morning drama, ''
The Ghost Writer's Wife'', as Yuichi Nishikori, an English teacher who will have a major impact on the lives of the heroines Toki Matsuno (
Akari Takaishi) and Heaven (
Tommy Bastow). His second morning drama is scheduled to air in the second half of 2025. ==Personal life==