Born in Shinjō, Yamagata, Togashi began drawing manga casually in his first to second year of elementary school. In high school, Togashi joined the fine-arts club; he later enrolled at Yamagata University where he studied education in the hope of becoming a teacher. During college he submitted some of his manga work to Weekly Young Jump, published by Shueisha. In 1986, at age 20, he authored a manga titled Buttobi Straight (ぶっとびストレート) for which he received the Tezuka Award, the most prestigious award for new comic artists in Japan. Another manga by Togashi, titled Jura no Miduki (ジュラのミヅキ), was an honorable mention in Shueisha's annual Hop Step Award Selection magazine in 1987. After having given up his goal of becoming a teacher, Togashi was contacted by an editor of Weekly Shōnen Jump during his senior year of college, who asked him to move to Tokyo.
Togashi's earliest published works for Shueisha included Ōkami Nante Kowakunai!! (狼なんて怖くない!!, lit. I'm Not Afraid of the Wolf!!), a collection of comedy manga short-stories. Weekly Shōnen Jump published some of the stories prior to a tankōbon release in 1989. Between 1989 and 1990, Togashi authored Ten de Shōwaru Cupid (てんで性悪キューピッド, lit. Altogether Wicked Cupid), a four-volume romance manga involving the affairs of a normal boy who meets and then gets stuck befriending a beautiful devil girl.
In 1990, Togashi made a name for himself with his next series YuYu Hakusho (幽☆遊☆白書, lit. Poltergeist Report). Based on his interests in the occult and in horror films, the plot features the character Yusuke Urameshi, a dead boy with an attitude and a high level of spiritual energy who eventually returns to life and spends his time defeating demons in the human world. The manga, which lasted 175 chapters over 19 tankōbon from 1990 to 1994, would go on to sell 40,000,000 copies in Japan, earn Togashi a Shogakukan Manga Award in 1994, and receive a hit anime adaptation. In 1995, he created Level E (レベルＥ), a science fiction manga depicting a fantastic universe in which extraterrestrials draw an innocent human into their rather strange intrigues. Comprising three volumes, it was first published in Weekly Shōnen Jump in 1995 and ran until 1997.
Togashi's next major series Hunter × Hunter (ハンター×ハンター), an action-adventure manga, began serialization in 1998. The story revolves around the protagonist Gon Freecss, a bright-eyed, good-hearted boy with talent who wishes to become a "Hunter", a person with fearsome skills bending all his formidable attention towards reaching a specific goal. Hunter × Hunter also performed very well commercially, with the first 20 volumes selling nearly 44,000,000 copies in Japan as of January 2008. In 2008, Togashi tied with One Piece author Eiichiro Oda as the fifth favorite manga artist from a poll posted by the marketing research firm Oricon.
- Sensēha Toshishita!! (1986, later featured in Ten de Shōwaru Cupid Volume 4)
- Jura no Miduki (1987, featured in Hop Step Award Selection Volume 1)
- Buttobi Straight (1987)
- Ōkami Nante Kowakunai!! (1989, tankōbon published by Shueisha)
- Tonda Birthday Present (1987, published in Weekly Shōnen Jump)
- Occult Tanteidan (1988–1989, two parts published in Weekly Shōnen Jump)
- Horror Angel (1988, published in Weekly Shōnen Jump)
- Ōkami Nante Kowakunai!! (1989, published in Weekly Shōnen Jump)
- Ten de Shōwaru Cupid (1989–1990, serialized in Weekly Shōnen Jump)
- YuYu Hakusho (1990–1994, serialized in Weekly Shōnen Jump)
- Level E (1995–1997, serialized in Weekly Shōnen Jump)
- Hunter × Hunter (1998–ongoing, serialized in Weekly Shōnen Jump)
- Yoshirin de Pon! (1994, YuYu Hakusho dōjinshi distributed at 1994 Summer Comic Market)
- Official Hunter × Hunter Guide (2004, published by Shueisha)
- YuYu Hakusho Who's Who Underworld Character Book (2005, published by Shueisha)
- YuYu Hakusho Illustrations (2005, published by Shueisha)
- Oobo— Nu— Tochiibo— Nu— (2005, published by Kodansha)
- Interview with Masashi Kishimoto (Naruto)
- Interview with Eiichiro Oda (One Piece)
- Interview with Fujimaki Tadatoshi (Kuroko no Basket)
- Interview with Sui Ishida (Tokyo Ghoul)
- Interview in Volume 0
- North American Shonen Jump's interview with Yoshihiro Togashi
- Video Interview of Yoshihiro Togashi
- Jump Ryu Vol.21: Yoshihiro Togashi
- Profile at takeuchi-naoko.com
- Hunter x Hunter Story Board Exhibit at the Shinjō Mogami Manga Museum
- 2015 was Togashi's first year of not releasing any Hunter × Hunter chapters, likely due to health problems.
- A character named Togashi, appears in a couple of episodes in the 1999 anime.
- Togashi's family owns a paper store in Shinjō, Yamagata that is still open . His mother welcomes fans and sells limited edition Togashi goods.