San Dionisio is an administrative division in southern Metro Manila, Philippines. It is a barangay at the southwestern edge of Parañaque and north of its border with Manuyo, Las Piñas. The barangay is centered on the westernmost section of Dr. Santos Avenue where it veers north and parallels Elpidio Quirino Avenue with De Leon Street and Aldana Avenue forming its boundaries with La Huerta and Manuyo Uno respectively.