With the continuous improvement of people＇s living standard，household appliances and farm machines and tools have become the standard configuration of rural households，which causes a huge increase in rural power load． However，the development of rural power grid is still relatively lags behind，which does not match with the rapid growth of electricity load， and low voltage problem of rural power grids is very outstanding，which seriously affects the normal life and work of people． Applying voltage regulator to 10 kV line of rural power grid is an effective method for low voltage control with good effect and lower cost． The working principle of voltage regulator is analyzed，and through establishing the equivalent circuit of distribution line with 10 kV voltage regulator，the theoretical calculation of voltage regulator in 10 kV line is carried out． Combining with the practical situation of rural line，the installation effect of voltage regulator is verified，which provides a reference for low voltage control in rural power grid．