She performed in many Off-Broadway shows, including starring in a one-woman musical based on her life, titled It's Me, Sylvia!

[2] A documentary about her life titled I Was Always Sylvia aired on New York City public television channel WNET as part of The 51st State series.

[citation needed] In the early 1960s, she played the role of Sally Rogers in the pilot episode of what would become The Dick Van Dyke Show, which was later taken by Rose Marie for the series.

[2] Miles starred in Andy Warhol's underground feature film Heat (1972), [12] appearing in a lingering nude scene with Joe Dallesandro.

[15] Miles was also featured in the mainstream films 92 in the Shade, Critical Condition, The Great Scout & Cathouse Thursday, Crossing Delancey, and the 1989 comedy She-Devil, in which she played the mother of Meryl Streep's character.

[16][17] In her final years, Miles appeared in a few roles on television such as Sex and the City and One Life to Live, and in the films Go Go Tales and Wall Street: Money Never Sleeps.

"[18] In a New York restaurant in 1973, Miles publicly dumped a plate of food onto critic John Simon's head for his negative comments about her in a review of a play she starred in.

[19] Wayland Flowers and his puppet Madame first uttered the widely quoted line, "Sylvia Miles and Andy Warhol would attend the opening of an envelope".