Last name Ивао (Iwao 
, Ивао) , throughout the world, is quite a rare family name. The cognomen Ивао is characteristic of Japan, where it is quite a rare surname, Singapore, where it is a rare surname, and Malaysia, where it is a very rare surname. In absolute terms, the name is most common in Japan, China, and the United States. More prevalently, Ивао is the forename as well as the last name.