Ruben Sierra was an actor, best known for the films My Family, Seven Hours to Judgment, and The Secret Life of John Chapman.

Theatre credits include the Historical Event in How I Got That Story, Megs in The Strange Snow, and Satin in The Lower Depths (Chamber Theatre), La Patumiera in Primary English Class and Celso in the one-man show, I Am Celso (South Coast Repertory); and Philip Kastoria in Widows (Mark Taper Forum).

For L.A. Theatre Works, Ruben starred as God in Steambath, Juan/Doctor/Man in My Visits with MGM, and Alex Decostro/Indian Mike/Dream Interviewer/Others in Buk: The Life & Times of Charles Bukowski.

Ruben was also the founding Artistic Director of the Seattle Group Theatre.