The present disclosure has an object to provide a multicore optical connector that can achieve size reduction and pitch reduction without performing highly accurate machining of V-grooves or the like. The present disclosure is a multicore optical connector including a holding member 11 having a flat bottom surface 14B, and provided with a groove that enables a plurality of optical fibers 91 to be arranged along the bottom surface 14B, the plurality of optical fibers 91 stored in a row on the bottom surface of the groove, and a lid 15 that is in contact with all the plurality of optical fibers 91 and is fixed to the plurality of optical fibers 91 and the holding member 11 in a state in which the plurality of optical fibers 91 are pressed against the bottom surface 14B of the groove to form a long hole 12 at the groove 14.