The Río Ameca is a river of some 230 km in length in western Mexico. It rises in the Bosque de la Primavera in Jalisco, 23 km to the west of state capital Guadalajara; flows through the city of Ameca; and then forms the boundary between Jalisco and Nayarit on its way to the Pacific Ocean, where it drains into the Bahía de Banderas near Puerto Vallarta, Jalisco.