Abstract: In order to study the operating efficiency of insurance companies, this paper uses the operating data of insurance companies from 2016 to 2018 to calculate and analyze the operating efficiency of four kinds of large-scale insurance companies through the three-stage DEA model. The results show that after excluding environmental variables such as years of establishment, company nature and broad money growth rate, the operating efficiency value of the insurance industry changed from high to low to large, medium, small and micro insurance companies. It is concluded that the adjustment of external environment has great influence on the study of insurance industry operation efficiency. The comprehensive efficiency of insurance industry is at a low level. Although it is increasing year by year, it still fails to reach DEA effectiveness. Pure technical efficiency is relatively stable, and scale efficiency is the main reason for its low operating efficiency. According to this, the government should further optimize the external environment and perfect the current supervision system. Insurance companies shall vigorously introduce management talents and insurance specialists from the insurance industry. Small and micro insurance companies shall learn more advanced experience from large and medium-sized insurance companies and strengthen their innovation capacity. In addition, insurance companies need to combine their current status, optimize the scale of assets, improve management efficiency, integrate high-quality resources through merger and reorganization, and transform to a large group of insurance companies, so as to ensure that enterprises can realize increasing returns to scale.