The Merizo Conbento is a historic building on Guam Route 4 in Merizo, Guam. Built in 1856, it is the oldest known occupied building on the island. It is a two-story concrete and ifil-wood structure with a gabled corrugated-metal roof, and a large set of concrete stairs leading to the main level above a raised basement. The present-day exterior is a faithful representation of the building's original appearance (with the exception of the roofing material, and original walls of manposteria remain inside the structure. It was built as a parish house for the local Roman Catholic diocese, and saw use as a military post and prison during the Japanese occupation period during World War II.