The transnational patent cooperation network in the field of digital communication under the background of the "Belt and Road" is taken as the research object, and social network analysis is used to study the status of patent cooperation of China and the areas along the "Belt and Road" in the field of digital communications from 2000 to 2019, and the evolutionary characteristics of patent cooperation networks in the field of digital communications in terms of the network status, structural holes, small world effects, the connection of the two-mode network of "patent holder-hot technology" ,etc are analyzed. The results show that the uneven geographical distribution of patent cooperation between China and the "Belt and Road" sectors has increased. The centralization degree of network is declining, and the centralization status of Singapore, the former core country, is declining, while that of China, India and Russia is gradually rising. Patent cooperation network has small world effect, but in recent years, the small world effect is weakening, affecting the stability of the network. The decrease of centrality and structure hole index of China and Singapore in the network indicates that the influence of China and Singapore on network cooperation resources and cooperative relationships is weakening. There are fewer strong enterprises in China that can carry out extensive patent cooperation in hot technology fields, and the width and depth of patent cooperation in hot technology fields need to be strengthened. A theoretical basis for China''s future strategy of digital communications transnational patent cooperation with regions along the "Belt and Road" is provided by the results.