The 42-year-old actress shot to fame playing Rachel McGuire in the 90s ABC sitcom, also appearing in "Home Improvement," "Rules of Engagement" and 2004 film "White Chicks."
Maitland said she now "felt ready" to move into the adult film industry with a new feature-length movie "Drive."
Speaking to In Touch Weekly, she explained: "They asked me to be a part of this, and I thought, 'I never knew there was anything in adults or porn or whatever that was this well done.'"
"I read the script, and I was like, 'This is really, really well written. This has so many themes in this and just my character is so different than anything I have portrayed before.'"
The redhead beauty, who has been shocking fans with sizzling, half-naked selfies on social media for years, went on to admit that she had been considering venturing into porn for a while.
She shared: "I felt ready. It wasn’t like I was saying, 'Oh, I want to do this all along,' but it was like, ‘I need to do this'
"I really feel that quality stuff and the hot sex stuff can be together, and I really want that."
Maitland signed to adult boutique talent agency Society 15 earlier this year, and remained defiant as she insisted that she "doesn't give a f---" about discussing her X-rated role.
The actress said: "I want to be who I am, and I just think as I have matured too, I am who I am."
Maitland has advertised "Drive" on her Instagram page, which has 680k followers.
Fans were shocked by the saucy promo, with one writing: "Is she a porn star???"
Another added: "Can not believe I just found out you do porn."
A third made cheeky reference to "Boy Meets World" character Topanga, asking: "Why can't Topanga be part of his too??"
"Boy Meets World" premiered in 1993, following schoolboy Cory Matthews, his best friend Shawn, love interest Topanga and brother Eric as they navigated the trials and tribulations of growing up.
Maitland made her debut at age 21 in 1998, starring as Eric and his best pal Jack's roommate, Rachel, from Season 6 onwards.
The series came to an end in 2000 but was rebooted as "Girl Meets World" in 2014, with Cory an Topanga's daughter Riley the show's new main character.
Several original "Boy Meets World" cast members made cameos in the series, which aired for three years, but Maitland never reprised her role.