Title: Mary Jane Watson
Passage: MJ eventually returns, her behavior showing a marked change with her abandonment of her false front. Following an attack on Peter by Puma, she breaks down and admits her knowledge of Peter's secret identity in The Amazing Spider-Man #257. After learning of her own family history in The Amazing Spider-Man #259, Peter finds a new respect for her and begins to truly understand her. MJ makes it clear to Peter that knowing his identity changes nothing about her feelings, and that she only loves him as a friend.
Question: does mary jane know peter is spider man
Answer: yes