He liked acting as a child at school, but only at his second attempt did he make it to DAMU (Theater Academy). While still a student, he played as a guest actor at the Na Zábradlí Theater, where he accepted a permanent engagement in 1966. After the dissolution of this theatre, he moved to the Vinohrady Theatre (1991). He became well known in a number of productions by Jan Grossmann and Ewald Schorm. In 1978, he won the Literary Fund Award for the leading part in Hamlet.

He also appeared in movies as a student. In 1965, along with Dana Syslová, he was chosen for the lead role in the comedy The Length of a Kiss, Ninety. His more prominent roles in other movies proved that there are no small roles: even in small parts, he could create memorable characters: e.g. in the comedies such as Seclusion Near a Forest, My Sweet Little Village, or in the drama Death of Beautiful Roebucks. He also starred in several series (Maturity Tests, Chef Svatopluk’s Confusion). He is well remembered from the TV series The Land Gone Wild, An Unsigned Button, or in the films Nice Moments Without Guarantee, ROMing, Three Brothers, Fairy Tales for Emma, and his last film, I Love You Blue. In the 1980s, he also made a significant impact in dubbing.

A few years ago, Oldřich Vlach had to part with his work in the theatre. His post-surgery conditions and spinal problems have made it impossible for him to return to the stage.