Jorge Alberto Mendoza, 34, of Novato, was arrested at 1:40 a.m. today at the girl's Novato home, Sgt. Keith Heiden said.
The girl told police on Friday that she had been involved in a sexual relationship with Mendoza, whom she met at a local store, Heiden said.
The girl arranged to meet with Mendoza at her home this morning and Mendoza was arrested when he arrived, Heiden said.
Mendoza was booked into jail on six felony charges including unlawful sex with a minor and committing lewd acts with a child under age 14.
His bail was set at $100,000 and there is also a U.S. Immigrations and Customs and Enforcement hold on him, Heiden said.