Abstarct: The use of renewable resources has been significantly developed over the last decades. In addition to reducing the environmental pollution by these types of resources, the structure of their connection to the network causes to reduce in the network power losses and also the energy waste. In the recent years, solar power plants baxsed on photovoltaic module have become more capable of generating the human requirement energies, because of the simplicity in installing of the power plants structures. In this study, in order to increase the efficiency of these types of power plants, a stable adaptive controller has been designed for solar power plants with micro-inverter structure. The suggested controller maintains the THD rate of the micro-inverter output constant by matching its parameters. It should be noticed that, in order to display the performance of the micro-inverter and suggested controller, the modeling of both inverter and stable adaptive controller was performed by using MATLAB simulator. At the end, it is shown that by adjusting the adaptive controller and ensuring the stability of the whole system, the performance of this controller, is very good in pursuit of the desired THD rate of the micro-inverter output.