Mambusao is a third class municipality in the province of Capiz, Philippines. According to the 2010 census, it has a population of 37,672 people. Its economy is based on agriculture with rice and coconut as the primary products and crops.
The annual festival of Mambusao is called "Inilusan" honoring of St. Catherine of Alexandria, the patron saint of the town, celebrated every November 25. Inilusan literally means sharing of dish by neighbors.