Jenkins shot 7-under 63 in the final round at The Golf Center at Kings Island, and Thorpe shot his second straight 65 to finish at 10-under 130 in the rain-shortened 36-hole event.
The $1.5 million tournament was shortened to two rounds because of heavy rains Friday.
It was the first win this year for Thorpe, and his third on the Senior Tour. He earned $225,000.
It was also a bit of revenge, as Jenkins defeated Thorpe in a playoff in the 1999 Bell Atlantic Classic.
Full-field scores from the Kroger Senior Classic