The invention discloses a cabinet door detection device, an opening and closing detection circuit and an openable cabinet. The opening and closing detection circuit comprises an opening and closing detection module and a signal output end, wherein the opening and closing detection module comprises a signal transmitting end and a signal receiving end, and the signal receiving end adjusts the state according to the received signal transmitted by the signal transmitting end; and the signal output end is connected to the signal receiving end of the opening and closing detection circuit, and is used for outputting a corresponding level signal according to the state of the signal receiving end of the opening and closing detection module. The opening and closing state of a cabinet door is detected in a noncontact electrical mode, and compared with the existing micro switch detection, the loss of machinery can be reduced, so that the service life of equipment is prolonged.