The lighting accidents of distribution transformer in qinzhou of Guangxi occur seriously so that it is required to reform the lighting protection. Based on the field investigation and experiments of measuring the earth resistance, it is proposed by relevant theory that the distribution transformers suffering lighting strike is due to the defective lighting protection, including unequipped low voltage arresters,problematic earth device and earth resistance beyond standard value. Based on the analysis, some measures are proposed such as installing low voltage arresters, connecting the coilout at low voltage side with cable and overhead line, reforming earth device and reducing the ground resistance.