An optical connector has a front end and a rear end in a first direction. The optical connector includes a ferrule that holds an optical fiber at the front end, and a front housing that accommodates the ferrule. The ferrule includes a flange portion having a regular hexagonal prism shape. The front housing has a through-hole into which the flange portion is inserted. The through-hole includes a first hole portion in which a cross section perpendicular to the first direction is a regular hexagonal shape, and a second hole portion that is continuous from the first hole portion. The second hole portion has a third end close to the front end, and a fourth end close to the rear end. In a cross section of the fourth end perpendicular to the first direction, six contours corresponding respectively to six sides of the third end bulge outward or inward.