A USB connector comprises a special USB plug and a USB receptacle mateable with the special USB plug. The special USB plug has a plug ground contact and a plug contact portion as a part of the plug ground contact. The USB receptacle has a plurality of contacts including a ground contact, a detector and a holding member. Each of the contacts has a contact point. Especially the ground contacts has the contact point configured to be brought into contact with the plug ground contact while the detector has a detecting portion configured to be brought into contact with the plug contact portion. The holding member has a plate portion formed with a principal surface. The holding member holds the contacts so that the contact points project from the principal surface of the plate portion while holding the detector so that the detecting portion projects from the principal surface of the plate portion. A distance between the detecting portion and the contact point of the ground contact is smaller than a distance between the detecting portion and the contact point of the contact other than the ground contact.