As the establishment of protected areas in China entered a new development stage, national parks have been recognized as the main body of a new system of protected areas. Realization of management objectives requires a large number of monitoring data and information, so the monitoring of national parks has been given great significance. However, the pilot national parks were established through integration of different types of protected areas, so they were facing the challenge of the integration of different types of monitoring. Specific problems include inconsistent monitoring indicator systems, ineffective monitoring data management, flawed monitoring implementation mechanism, and so on. Firstly, this paper analyzed the monitoring status and needs of protected areas in China and found that such problems existed in the monitoring of protected areas as different monitoring priorities, redundant monitoring data and diverse monitoring departments. Then, this paper sorted out the monitoring practice and experience of foreign national parks and found that most monitoring systems of national parks in other countries took the long-term ecological monitoring as the core, established a top-down monitoring implementation mechanism, designed a monitoring indicator system with both consistency and difference, and emphasized effective data management and utilization. Under the basic idea of integrating and optimizing various types of protected areas, learning from the monitoring practice and experience of foreign national parks, and considering the monitoring status and needs of protected areas in China, this paper constructed a comprehensive monitoring system for national parks in China from the top-level design. The system is based on natural resource inventory, centered on ecological monitoring, assisted by natural and human interference monitoring, and supplemented by management effectiveness monitoring that serves the evaluation of management effectiveness. The natural resource inventory is used to determine the baseline of conservation and management, the ecological monitoring is applied to learn the rules of ecosystem changes, the natural and human interference monitoring helps clarify the correlation mechanism, and the management effectiveness monitoring serves the evaluation of management effectiveness. On this basis, the paper further proposed an implementation mechanism for the national park monitoring, which is composed of three-level monitoring network, monitoring data management, and management effectiveness evaluation. In the "nation-province-national park" implementation mechanism, on the one hand, a unified monitoring database system and management platform should be established to realize the storage, management and analysis of monitoring data; on the other hand, the management effectiveness evaluation system should also be set up, to promote the monitoring data to serve the conservation planning and management of national parks. The paper made an important attempt in the construction of the national park monitoring system, and is expected to provide a useful reference for the establishment of the national park monitoring system and implementation mechanism in China.