Yap is a many-time member of the RP Basketball Team. Yap was a member of the Philippine National Team that played at the 2003 Southeast Asian Games where they won the basketball gold. He was also a member of the national team that participated at the 2009 FIBA Asia Championship where he played 8 of the 9 games posting averages of 9.3 ppg (74 total points), 2.6 rpg (21 total rebounds) and 0.9 assists (7 total assists). The team ended up in 8th place. In the 2009 Southeast Asia Basketball Association (SEABA) Championships, Yap was a member of the Powerade-Team Pilipinas that won the said tournament, beating Indonesia in the Finals, 98–68.