A connector includes contacts arranged in a contact-arrangement plane and including a source contact and a signal contact, each of the contacts having a contact portion that comes into contact with a contact of a counter-connector, a ground plate made of metal disposed in parallel with the contact-arrangement plan, an insulator that holds the contacts and the ground plate, and a shell that covers an outer periphery of the insulator and is made of metal, the ground plate being disposed so as to face the contacts through a portion of the insulator with the contact portion of each contact being exposed, and having a cutout formed at an end of the ground plate adjacent to the contact portion of the source contact, and the insulator having a projection that fills the cutout of the ground plate.