Inverter control technology is the core technology of photovoltaic power generation system. In this paper, an improved deadbeat control strategy for photovoltaic grid-connected inverter was proposed and implemented in TMS320F2812 system. DC input voltage, output current and grid voltage are introduced in the improved deadbeat control strategy for getting the duty value, which is used to control the power switch by unipolar & frequency multiplication SPWM. The improved control strategy can effectively restrain the influence of DC input voltage and power fluctuation on grid and the whole system. The inverter output waveforms have high quality and low harmonic component. The results of simulation and experiment have proved the validity and practicability of this improved control strategy.