After graduating in acting at AIU in Ljubljana in 1957, the drama actress, poet and writer Alja Tkačev worked as a freelance artist. She established a theatre company Komedijantski atelje and worked as a teacher at the youth centre Center za estetsko vzgojo mladine in Ljubljana. In the period between 1964 and 1980, she was a member of the Slovenian Youth Theatre, and from 1983 a member of the Ljubljana Puppet Theatre. She also appeared in alternative theatres, TV and film.
Much like her career, her roles were also diverse, because she portrayed children, boys and girls, as well as contemporary women and grotesquely mocked characters of unrealistic creatures. She also appeared on television, frequently in youth television shows and plays, in numerous Slovenian films, regarded today as classics. She translated drama texts and wrote for theatre, also poetry and prose.