Khadijah Farmer, 27, said the incident happened June 24 at Caliente Cab Company on Seventh Avenue South, where she had gone with her girlfriend and another friend to have dinner after the march.
Farmer said she was using the women's bathroom when a male bouncer burst in and banged on the stall door, saying a customer had complained that there was a man in the women's room.
"I said, 'I am a woman and I am where I am supposed to be,"' Farmer said. "I offered to show him some identification. I was told that's neither here nor there."
Caliente Cab Company, a Mexican restaurant known for its enormous margaritas and checker-cab decor, did not immediately return a call for comment.
Farmer said the bouncer escorted her to her table and forced her party to pay their check and leave.
"I felt embarrassed and humiliated," said Farmer, a Manhattan resident who works as a counselor at a residential program for people with disabilities. "I'm just hurt that even my wanting to prove that I'm female wasn't enough."
Farmer is being represented by the Transgender Legal Defense and Education Fund, which is demanding that the restaurant train its staff not to discriminate on the basis of gender identity and expression.
New York City law prevents discrimination on the basis of gender identity.
Farmer is not a transgender person, but she said her appearance is masculine enough that she is sometimes mistaken for a man.
"I'm never upset with that," she said. "I say very kindly, 'I'm female.' Usually I get, 'I'm so sorry."'