Abstract: Based on the research background of photovoltaic power grid without government subsidy, this paper takes Yunnan province and the electricity consumption law of farmers as the base. the economic benefit analysis model of photo voltaic-energy storage system is established.Taking project revenue and static payback period as economic benefit evaluation indexes, the influence of different energy storage costs and installed scale on system revenue was analyzed. Based on the evaluation results, suggestions are put forward to promote its development. The case shows that the installation of energy storage system will increase the initial investment of the system capital, but the total income of the project has increased, the payback period of investment has also been shortened, and there is no economic advantages without energy storage system.