Park won the Walmart Northwest Arkansas Championship, topping Ryu So-yeon on the first hole of a sudden-death playoff. It was Park's 13th professional win and eighth LPGA title overall.
She has held the No. 1 place in the rankings since April 15.
Earlier this year, Park won the Kraft Nabisco Championship and the LPGA Championship. She'll go for a third major this week at the U.S. Women's Open in Southampton, N.Y.
If Park can win her second U.S. Women's Open -- she won previously in 2008 -- and then takes the British Women's Open in August, she would be the first to win the women's golf Grand Slam.
She needs the British title to complete the career Grand Slam, a feat managed by just six players. Three players -- Babe Zaharias (1950), Mickey Wright (1961) and Pat Bradley (1986) -- have won three majors in a year.
The only change this week in the women's golf Top 10 has Feng Shanshan moving past Yani Tseng for the No. 6 spot. Tseng is seventh.
The world women's golf Top 10, listing player, home country and rankings points average:
1. Inbee Park, South Korea, 12.04
2. Stacy Lewis, United States, 8.52
3. Suzann Pettersen, Norway, 8.17
4. Choi Na-yeon, South Korea, 7.71
5. Ryu So-yeon, South Korea, 7.04
6. Feng Shanshan, China, 6.30
7. Yani Tseng, Taipei, 6.15
8. Karrie Webb, Australia. 6.12
9. Jiyai Shin, South Korea, 5.99
10. Ai Miyazato, Japan, 5.63