He graduated in 1970, and in 1972 then joined the East West Players, the oldest Asian-American theater company in Los Angeles.

His many television movies have included the film adaptation of Farewell to Manzanar (1976) about Japanese-American internment during World War II.

(Kusatsu also guest-starred on an episode of Lou Grant about Japanese internment in the U.S.) Other television films and mini-series have been And The Sea Will Tell, and American Tragedy playing Judge Lance Ito.

Kusatsu had roles in Dragon: The Bruce Lee Story (1993), In the Line of Fire (1993), and in American Pie (1999).

Other films include Shopgirl as Mr. Agasa, and in Sydney Pollack's The Interpreter (2005) as Lee Wu, chief of security for the United Nations Headquarters.

He also had a role opposite Glenn Close in Bruce Beresford's World War II drama Paradise Road (1997).

He was Grandpa Ted in Season 2 of Netflix' Never Have I Ever, and was in episodes of Young Rock, Days of Our Lives, and The United States of Al.