Hitomi Shimizu is a composer of live action films, television programs, animated shorts and videogames. Her score for the 2001 comedy Waterboys, composed with Gakuji Matsuda, won the Japan Academy Prize for best film score.

She also contributed music to the short animation films by Kōji Yamamura, such as Mt.Head which won the top prize at the 27th Annecy International Animation Film Festival, and was nominated for OSCAR  2002 for Best Animated Short Film. That film also won the Best Soundtrack Creation Award at the Clermont-Ferrand International Short Film Festival.

Hitomi is part of a musical duo with violinist Hiromi Nishida called Syzygys.

Syzygys' albums are reissued by producer, John Zorn on his Tzadik label. 

Syzygys wrote original score for  Netflix film "Dick Johnson Is Dead" directed by Kirsten Johnson who won Primetime EMMY 's best direction for the documentary film 2020.

Hitomi also specializes in horror music such as Playstation "SIREN" series. The theme song "Hoshin Goeika" is well known as " the scariest song" in the horror game world.

Microtonal music is her life work. With her self-made microtonal reed organ ( Harry Partch's 43tone scale), custom made Tonal Plexus keyboard, and the Vietnamese Dan Bau, she makes solo performances in Japan.