The countries along the 21st-Century Maritime Silk Road (MSRCs) are important geo-economic spaces for China. The implementation of the Belt and Road initiative is drawing a new geo-economic network of the Maritime Silk Road. Based on trade and investment flows, this study uses social network analysis to examine the characteristics and structure of trade and investment networks between China and the MSRCs. The results show that the MSRCs’ trade network is approximately an irregular quadrilateral, the node weighted degree distribution follows the law of long-tail distribution, and the trade network has shifted from the tripartite confrontation of China, Japan, and South Korea to China’s single-core dominance. The MSRCs’ trade group has changed greatly, and the trade cohesion of China, Japan, and South Korea is strong. The MSRCs’ investment network is not fully developed and the network connections are sparse. China, Japan, and Singapore are its core nodes. The weight degree of the MSRCs’ investment inflow network first increased and then decreased, and the weight degree of the MSRCs’ investment outflow network increased. The MSRCs’ investment network followed the “core-peripheral” structure. The cohesive subgroup of the investment inflow network did not have significant regional characteristics, and the cohesion of the core subgroups in the MSRCs’ investment outflow network was strong. To promote the development of geo-economic relations between China and the MSRCs, China should focus on regional powers, upgrade the investment network of MSRCs, and implement differentiated geo-economic cooperation strategies.

As a great practice of building a community of shared future for mankind, the Belt and Road Initiative is facing geopolitical risk brought by great power games, regional conflicts and terrorism. It is an important mission of geopolitical research to scientifically deal with the geopolitical risk along the Belt and Road. This study systematically constructs the geopolitical risk assessment index system and analyzes the spatiotemporal evolution, obstacle factors and risk types of geopolitical risk of countries along the Belt and Road by using the entropy weight TOPSIS model, obstacle degree model and minimum variance method. The research results showed that: (1) From 2005 to 2020, the polarization of geopolitical risk in countries along the Belt and Road was very significant, and the overall trend of geopolitical risk tended to deteriorate. (2) The Middle East and Eastern Europe were the most important geopolitical risk zones along the Belt and Road, and Afghanistan, Iraq, Russia and Ukraine were the main high geopolitical risk centers, with significant risk spillover effects from these centers. (3) Terrorism and close relations with the United States were the most important obstacle factors for geopolitical risk in countries along the Belt and Road, and military intervention politics, trade dependence degree and foreign debt burden were important obstacle factors for geopolitical risk in countries along the Belt and Road. (4) Geopolitical risk along the Belt and Road can be divided into sovereign risk dominant type, sovereign and military risk dominant type, sovereign and major power intervention risk dominant type, and sovereign and military and major power intervention risk jointly dominated type, among which sovereign and military and major power intervention risk jointly dominated type was the most important geopolitical risk type. In order to scientifically deal with geopolitical risk in countries along the Belt and Road, it is necessary to strengthen geopolitical risk awareness, pay attention to the dominant geopolitical risk factors, strengthen the control of regional geopolitical risk spillover and formulate reasonable risk prevention and control scheme based on geopolitical risk types.