Analysis on China's international research collaboration from the point of output of international collaboration research projects is of great significance to the formulation and optimization of international research collaboration policies and management regulations for science and technology policy makers and research managers. This paper studied the output papers of the project supported by major international (regional) joint research program funded by NSFC in 2001-2018 and analyzed the characteristics of China's international research collaboration with methods of bibliometric, social network analysis and BCG Matrix analysis. The output papers of the project supported by major international (regional) joint research program funded by NSFC have been steadily rising. From the perspective of the overall collaboration network, it showed that there are 99 countries participating in the collaboration and the collaboration network has a high degree of connectivity and grouping. However, the network density is not high, and the new partnership needs to be further established. From the perspective of time evolution and subject areas, it is slightly different for the international research collaboration network at each stage and across various subject areas. The level of collaboration is uneven between different countries and the number of developing and prosperous countries is relatively more. The countries with more prominent collaboration with China include the United States, Britain, Australia, Canada, Germany, Japan, Sweden, etc., especially United States, and each subject has its own characteristics. China has played an important leading role in international research collaboration of China’s international collaboration research project funded by NSFC. The international collaboration leaded by China are mainly bilateral collaboration, while multilateral is relatively rare. It is suggested that China should further enhance the depth and breadth of international research collaboration, focus on collaboration with various countries in the field of specialization, and optimize the bilateral and multilateral international research collaboration mechanism.