A composite heat adjusting device, comprising: a plurality of heat plates, each of the plurality of heat plates including a substrate and a heating unit, the substrate including a body and an installation element disposed on any side of the body, the heating unit including a circuit board disposed in the installation element and including at least one heating element disposed on the body and electrically connected to the circuit board; and a plurality of electrical connection members, each of the electrical connection members including a connection base and a plurality of connection portions disposed on the connection base, the connection portions being electrically connected through the connection base, wherein the installation element of each heat plate is extended to form an installation recess at any corner of the heat plate, each circuit board includes a plurality of connection terminals extended to the installation recess, and the connection terminal is connected to the corresponding connection portion of the electrical connection member, so that the heat plates are electrically connected to each other, characterized in that a plurality of terminal holes for insertion of the connection terminals in a direction perpendicular to the heat plate are disposed on the connection portion of the electrical connection member, the composite heat adjusting device includes multiple electrical connection members, a recessed connection hole and a protruding connection pin are disposed on the connection base of each electrical connection member, and the electrical connection members are correspondingly coupled to insert the respective connection pins in the respective corresponding connection holes. a plurality of heat plates, each of the plurality of heat plates including a substrate and a heating unit, the substrate including a body and an installation element disposed on any side of the body, the heating unit including a circuit board disposed in the installation element and including at least one heating element disposed on the body and electrically connected to the circuit board; and a plurality of electrical connection members, each of the electrical connection members including a connection base and a plurality of connection portions disposed on the connection base, the connection portions being electrically connected through the connection base, wherein the installation element of each heat plate is extended to form an installation recess at any corner of the heat plate, each circuit board includes a plurality of connection terminals extended to the installation recess, and the connection terminal is connected to the corresponding connection portion of the electrical connection member, so that the heat plates are electrically connected to each other, characterized in that a plurality of terminal holes for insertion of the connection terminals in a direction perpendicular to the heat plate are disposed on the connection portion of the electrical connection member, the composite heat adjusting device includes multiple electrical connection members, a recessed connection hole and a protruding connection pin are disposed on the connection base of each electrical connection member, and the electrical connection members are correspondingly coupled to insert the respective connection pins in the respective corresponding connection holes.