In 2009 Eun-Hee Ji won the U.S. Women's Open with a birdie putt on the final hole for her first LPGA major championship victory. She also tied for sixth at the MasterCard Classic Honoring Alejo Peralta and the LPGA State Farm Classic, where she carded a career-low 63 in the final round. Tied for 10th at the SBS Open at Turtle Bay, tied for 14th at the HSBC Women's Champions and tied for 15th at the Honda LPGA Thailand. Crossed the $2 million mark in career earnings with a tie for 27th at the Evian Masters Presented by Societe Generale.

In 2008, became a Rolex First-Time Winner at the Wegmans LPGA; recorded seven additional top-10 finishes; crossed the $1 million mark in career earnings with a tie for eighth at the Samsung World Championship.

In 2007, best finish was second place at the Hana Bank KOLON Championship 2008; won the Phoenix Park Classic and the KB Star Tour in Hampyung on the Korea LPGA (KLPGA).

In 2006, played on the KLPGA with four top-10 finishes; also played on the Asia Tour, where she won two events, including the Macaoh Open and the Malaysia Open; tied for 34th at the LPGA Final Qualifying Tournament to earn non-exempt status for the 2007 LPGA season.