Since Jiri National Park was designated as the first national park in 1967, Korean protected area system with national parks as the core part has undergone more than 50 years development. A lot of management experiences have been achieved in the construction process of Korean national parks, which deserves China to learn from it. In this study, the Three-River-Source National Park (the first national park in China) and the Jiri National Park (the first National Park in South Korea) were chosen as study cases and both qualitative and quantitative analyses were applied to reveal their differences in management capacity. Evaluation method on the management capacity of national parks based on the best practices was used in the quantitative analysis where comparisons in both the comprehensive and individual management capacity were made between the two cases. Main conclusions were drawn as follows. Firstly, the comprehensive scores of management capacity of Three-River-Source National Park and Jiri National Park were 68.03 and 86.59, respectively. The gap in the management capacity between the two cases existed in five aspects of the institutional construction, guarantee mechanism, natural resources and environment management, community management, and popular science and education. Secondly, the individual management capacity of Jiri National Park was outstanding in resources baseline survey, legal system, multi-stakeholder participation, environmental education, and tourism management, which could provide useful reference for the Three-River-Source National Park. Thirdly, Three-River-Source National Park had comparative advantages in the individual management capacity of ecological compensation and restraint system, while its disadvantages in natural assets registration, resources survey, community organization, and tourism management needed to be improved urgently. Based on the results, suggestions were put forward for improvement of the management capacity of Three-River-Source National Park like strengthening the support of scientific research, improving the mechanism of multi-stakeholder participation, and promoting the welfare sharing. Suggestions were also put forward for the construction of the national park system in China, namely, establishing the National Park Law and formulating top-level planning for the protected areas.