Off-site medical treatment refers to the behavior of patients to seek medical treatment in other areas outside the insured area. The policy of off-site medical treatment is a beneficial institutional arrangement to protect the rights and interests of insured persons and improve the fairness of health service utilization under the background of large population mobility and unbalanced distribution of high-quality medical resources in China. In the context of the continuous advancement of DRG/DIP payment reform, many problems in the implementation of off-site medical treatment are contrary to the objectives of DRG/DIP payment reform, and there are many inconsistencies. This paper introduces the current situation of the implementation of off-site medical treatment, systematically analyzes the problems existing in the implementation of off-site medical treatment, discusses the potential impact of existing problems on the reform of DRG/DIP payment methods, and proposes solutions. Strategies and recommendations provide a reference for accelerating the realization of DRG/DIP payment for off-site medical treatment.