Abstract: Based on the fuzzy analytic hierarchy process (FAHP), 14 evaluation indicators in four levels, including project establishment, on-site inspection, leak repair and retesting, and account management, were selected from the existing LDAR-related standards and technical guidelines in China, and a hierarchical structure model for LDAR implementation effect evaluation was constructed. By distributing more than 30 questionnaires to representatives of 3 types of groups: experts, enterprises, and third-party service providers, and then calculating the index weights, in order to solve the problem of how to scientifically assess the quality of LDAR implementation under the situation that the country pays more attention to the control of volatile organic compounds (VOCs).The results showed that the primary indicators in the assessment of LDAR implementation effectiveness were leak repair and retesting (0.305), project establishment (0.281), site inspection (0.245) and account management (0.169), and the 14 secondary indicators were ranked with the highest weight of leak repair timeliness and the lowest weight of compliance with exemption from inspection. The study established a systematic LDAR implementation effect assessment system based on the weight values and applied it to 10 enterprises in pharmaceutical, plastic products, synthetic resin and coating ink manufacturing, and concluded that the overall implementation effect of the pharmaceutical industry is preferred, the synthetic resin and coating ink industries have comparable implementation levels, and the compliance of plastic products enterprises in implementing LDAR work is slightly lower.