To provide a small and compact disconnector having a fixed contact and a movable contact, whose structure is improved so that parts can be commonly used for different rated currents.

The disconnector is composed of a pair of external terminals 2A, 2B arranged at both end parts of a mounting base 1, connected to a main circuit; a fixed contact 3 composed of a plurality of pairs of contact pieces 3A, 3B arranged at a right side and a left side, of which one end is connected to the external terminal, and each pair of the contact pieces faces the other through a gap; a rotary bridge-connection type movable contact 5 composed of a conductor block, arranged at the center of the gap so as to face the fixed contact; and a switching shaft 6 with an operating lever 7 connected to the movable contact. As a heat radiation means of a current conducting contact part, many slit grooves 5a are formed on a block peripheral face of the movable contact 5 excluding a contact face where the fixed contact piece contacts, and a heat radiation property each of the fixed contact and the movable contact is promoted by arranging a heat radiation fin 8 at every contact piece of the fixed contact. Applicability of current capacity at current conduction is to be widened by suppressing temperature increase of contact parts.