The 127 Hours star has played gay characters onscreen in films like Milk and Blind Spot, and he also famously shared a same-sex kiss with Will Forte on U.S. sketch show Saturday Night Live in 2009.
Many gossips have questioned the 34 year old's sexual orientation, and the actor insists he's not offended by all the speculation.
Franco, who has been romantically linked to his Spring Breakers co-star Ashley Benson, tells MTV.com, ""In high school these girls got mad at me and so they spread this rumour that I was having a gay relationship with one of my closest friends. And they even made up a little dance they would do in the girl's locker room about me being gay. I still don't know what the dance was...
""It wasn't like it was anything new. And, in fact, it wasn't something that frightened me... If people think that, it's fine. I really don't care.""