San Juan de Plan is a municipality located northeast of Plan in the province of Huesca, Aragon, Spain, in the foothills of the Pyrenees. According to the 2004 census, the municipality has a population of 147 inhabitants.The Romanesque church of the former abbey of San Juan Bautista, for which the community is named, was enlarged in the sixteenth century. The sixteenth-century abbot's house now houses the ethnographic museum.