Cognomen Хироо (Hiroo 
, Masurao , Хироо 
) , globally, is a rare surname. The family name Хироо is characteristic of Japan, where it is a rare surname, Thailand, where it is a very rare surname, and Indonesia. In absolute terms, the name is most common in Japan, China, and India. Likewise, Хироо is the forename as well as the last name.