[1] Yamashiro, who was originally from Kyoto, Japan, was born Yasuji Watanabe (渡辺 安治, Watanabe Yasuji),[1] but used Shingo Yamashiro as his stage name.

[1] Yamashiro starred in the television series Hakuba Dōji ("White Horse Rider"), beginning in 1960.

[1] During the 1970s, Yamashiro appeared in several yakuza films such as the Battles Without Honor and Humanity series[1] and Gambling Den Heist (1975).

Yamashiro also directed occasionally, helming such films in Nikkatsu's Roman porno series as Female Cats (1983) and Gemini Woman (1984).

[1] Yamashiro was admitted to a nursing home in Machida, western Tokyo, for treatment of diabetes.