Buenaventura "Bong" Mendieta Villamayor (born May 4, 1967) is a Filipino chess player.

He was awarded the title of Grandmaster by FIDE in 2000, becoming the fourth from the Philippines to achieve this feat.

He competed in the FIDE World Chess Championship 2000 in New Delhi, India.

In 2017, Villamayor transferred his national federation to represent Singapore.

[3] Bong Villamayor was a five-time participant in the Chess Olympiad: Villamayor also played at the 12th Asian Chess Championship held at Shenyang, China in 1999 where Team Philippines placed 4th but he won the Gold Medal in Board 2 where he posted 6.5/9 on the strength of 5 wins, 3 draws and 1 loss for a very high PR of 2602 as compared to his ELO then of 2447.