Call her Pippi Schlongstocking ... 'cause the actress who played the famous firecrotch in the 1988 movie is now starring in a hardcore sex tape being shopped around town, TMZ has learned.
The "star" of the tape is 39-year-old Tami Erin -- who played the freckle-faced red head girl in "The New Adventures of Pippi Longstocking" back in 1988 ... when she was 14.
We've seen the X-rated footage ... which appears to have been shot very recently and features Tami in various sexual situations -- most of which involve an unidentified penis.
And no, she's not wearing pigtails in the video ... you sick freaks.
So far, it's unclear if anyone has purchased the tape -- but we're guessing Steve Hirsch's ears just perked up.
So far, no comment from Pippi's people.