The development of cold chain logistics in the Yangtze River Economic Belt significantly supports China’s efforts to build a nationally and internationally connected “ four horizontal and four vertical” national cold chain logistics backbone network. This paper employs a policy-embedded comprehensive evaluation method based on the entropy weight method to construct an indicator system across three dimensions, measure the cold chain development level of each province and municipality, and analyze its spatiotemporal evolution characteristics. The results show that the overall development level of cold chain logistics exhibits an upward trend. Regional disparities gradually narrowed before 2020 but widened thereafter. Temporally, the cold chain development level of each province remained relatively stable over time, with Shanghai, Jiangsu, and Zhejiang consistently ranking in the top three. Spatially, the cold chain development level across the Yangtze River Economic Belt generally follows a pattern of “higher in the east and lower in the west”, with the downstream region significantly outperforming the midstream and upstream regions. Policy recommendations based on these findings can promote synergies and complementarities among different provinces and facilitate the integrated regional development of the Yangtze River Economic Belt.