The energy parameters of the photoelectric micro-power supply are analyzed based on the structure characteristics and the power consumption of wireless sensor nodes. Meanwhile, the design theory model of the micro-power supply is established by using the mechanism of the energy conversion, storage and transmission on the micro-power supply. In addition, the infection of the energy storage mode, distribute mode and the sensor node working mode on the system characteristics and the design parameters is analyzed by using the design theory model. The analysis results show that the energy management mode directly affects the design parameters and working characteristics of the micro-power supply. The design theory model and analysis results lay a theoretical foundation for optimization design of the micro-power supply on chip.