Banayoyo, officially the Municipality of Banayoyo (Ilocano: Ili ti Banayoyo; Filipino: Bayan ng Banayoyo), is a 4th class municipality in the province of Ilocos Sur, Philippines. According to the 2015 census, it has a population of 7,748 people. 

Settlements in the municipality are mostly established along the roads and in the areas near the people’s sources of livelihood. With limited economic opportunities in the municipality, some residents of the town have also left their town to seek higher education, better employment opportunities, better opportunities for trade and commerce not only to other more developed areas in the country but even abroad.