With climate change caused by massive greenhouse gas emissions emerging as an issue of global concern, it is urgent to improve carbon emission efficiency (CEE) for countries along the Belt and Road (BRI). The super-efficiency slacks-based measure (SBM) model is adopted to evaluate the CEE of 60 BRI countries from 2010 to 2019, while the Global Malmquist-Luenberger (GML) index, Theil index, and coefficient of variation (CV) are coupled to quantify the spatial and temporal variation and dynamic evolution of CEE. Subsequently, the spatial Durbin model (SDM) provides an empirical investigation regarding the impact of renewable energy investment and energy resource endowment on CEE given the spatial spillover effect. It is found that (1) From a static perspective, the CEE of BRI countries is generally poor and unevenly distributed in terms of temporal and spatial dimensions. The regional variation of CEE in Southeast Asia is narrowing, while it is widening in other regions. (2) Referring to the dynamic level, the GML index is featured U-shaped fluctuations, and both technical efficiency and technological progress contribute to the improvement of CEE in BRI countries. (3) The CEE of BRI countries exhibits significant spatial dependence, with high-high aggregation as well as low-low aggregation. (4) There is a significant positive influence of renewable energy investment on CEE in the country and neighboring countries, while energy resource endowment presents a remarkable adverse correlation. Consequently, it is suggested that the inter-regional cooperation among BRI countries should be strengthened to reinforce renewable energy investment, exert the technology and knowledge spillover effect sufficiently, and break the resource curse in the environmental field.