Policy No. 1439 allows all coal-fired units to enter the market, cancels the catalog price for all industrial and commercial users, and requires the power grid to purchase power temporarily on behalf of industrial and commercial users who have not entered the market, thus gives birth to the power grid agent purchase business under the new situation of the market. According to the requirements of policy No. 809 policy, the development process of power grid agent power purchase business and relevant business coordination among all departments of power grid is sort out, andseveral key issues in the key link of power grid agent power purchase business is analyzed . A set of calculation method of power purchase price by power grid agent is proposed, its impact on the operation of power grid companies is analyzed, and an example to further demonstrate the calculation method of power purchase price is constructed by power grid agent proposed, providing reference and technical support for the actual development of power purchase business by power grid agent.