Ao Manao (Thai: อ่าวมะนาว, pronounced [ʔàːw mā.nāːw]), meaning "Lime Bay", is a bay in the west side of the Gulf of Thailand.

It is open towards the east and is bounded by steep limestone outcrops forming peninsulas to the north and to the south.

There are two islands in the bay, Ko Lueam about 3.6 km offshore,[1] and smaller Ko Aen, about 1.5 km off the beach within the bay.

Ao Manao has a good beach which is a popular tourist destination.

It can be reached by road through the Wing 5 Royal Thai Air Force base.