Abstract: The rapid development and construction of new power systems have higher demands on the reliability assessment of distribution networks. The differentiated reliability requirements of end users in the distribution network and the operation characteristics of the power grid planning and operation stages are comprehensively considered, the classification standard of distribution network reliability level and a distribution network reliability assessment method suitable for planning-operation stages are proposed. First of all, various factors such as power consumption and user-side load characteristics are considered. The impact of the difference in reliability electricity price is taken into account, and from the system side, the user side and the power supply and consumption interaction side, an evaluation index system for the reliability of the power supply of the distribution network is established. Then the difference of end user's electricity demand expectation is considered, and the classification standard of distribution network reliability is proposed. Based on the above-mentioned classification standards and the differentiated reliability requirements of end users, a reliability assessment method for distribution network suitable for both planning and operation stages is proposed. Finally, an example analysis is carried out to verify the rationality of the proposed classification criteria and the effectiveness of the evaluation method.