"She told me she was 19," Taylor said in court as he admitted having sex with a prostitute who turned out to be a 16-year-old Bronx runaway.
Taylor was arrested in May at a hotel. He had previously pleaded not guilty to third-degree rape, patronizing a prostitute, sexual abuse and endangering a child.
He had been resisting a plea deal for months.
According to prosecutors, Taylor had been offered a six-month jail term and 10 years of probation in exchange for pleading guilty to a felony. In that case, Taylor would have also had to register as a sex offender. His defense team turned that offer down, calling it unacceptable.
Taylor was inducted into the Pro Football Hall of Fame in 1999. He also competed in ABC's "Dancing With the Stars" in 2009.
The Associated Press Contributed to this report.