Api Chamber is a chamber in Whiterock Cave in Mount Api, Gunung Mulu National Park, Sarawak, Malaysia. Measuring 300 m by 200 m and with a surveyed circumference of 900 m it is the ninth largest cave chamber by area in the world. Its height is over 100 m and its plan area is 58,000 square metres. It is the second largest chamber in Malaysia, after Sarawak Chamber.