The invention relates to a double-core ventilation heat exchanger heat recover device which comprises a machine body, a first ventilation fan, a second ventilation fan, an overall gravity aluminum alloy porous microchannel heat pipe heat exchanger and a plate heat exchanger. The overall gravity aluminum alloy porous microchannel heat pipe heat exchanger and the plate heat exchanger are arranged in the machine body. Inner space of the machine body is divided by the plate heat exchanger into a left part and a right part. The right part of the inner space of the machine body is divided into a first channel and a second channel. The overall gravity aluminum alloy porous microchannel heat pipe heat exchanger is arranged in the left part of the inner space of the machine body. By means of the design of the overall gravity aluminum alloy porous microchannel heat pipe heat exchanger and the plate heat exchanger, fresh air is pretreated through exhaust energy, and therefore the aim of energy recovery is achieved.