Thirty-two-year-old Kevin Kaylor, of Elizabethtown, Lancaster County, filed the lawsuit Monday in Fayette County. He's incarcerated at the State Correctional Institution-Fayette.
Kaylor says Yahaira Molina, of Lancaster, happily accepted the ring when he proposed to her during a prison visit in September 2008 - but that he hasn't heard from her since. Kaylor says a sibling helped him buy the ring a few days earlier.
Court records show Kaylor pleaded guilty and was sentenced in April 2008.
A telephone number listed under Molina's name was disconnected Tuesday.