The invention discloses a composite energy collection circuit. The composite energy collection circuit is characterized by including a temperature difference power generation sheet, a piezoelectric sheet, a positive-negative peak detection module, a zero potential switching module, a first inductor, a first diode, a first energy storage capacitor, a second energy storage capacitor and a load; thecomposite energy collection circuit has the advantages that the first inductor is in serial connection with a parasitic capacitor in the piezoelectric sheet and the first energy storage capacitor, inthis way, LC oscillation is generated, charges accumulated on the parasitic capacitor in the piezoelectric sheet and the first energy storage capacitor are transferred to the first inductor, at the moment when currents on the first inductor reach the maximum, through the positive-negative peak detection module, a first PNP transistor or a second PNP transistor is immediately disconnected, and thenall energy stored in the first inductor flows to the load and the second energy storage capacitor through the first diode. The whole composite energy collection circuit is a completely self-startingand self-powered circuit and can continually collect temperature difference electric energy and piezoelectric vibrational energy in a current environment, therefore, the energy collection efficiency of the whole composite energy collection circuit is improved, and the application cost is reduced.