Under the background of "double carbon”, this paper utilizes the panel data of 30 provinces in China from 2010 to 2020 to construct a spatial Durbin model, in order to study the spatial spillover effect of industrial cooperative agglomeration on carbon emission intensity. The results of the study show that industrial cooperative agglomeration has a significant impact on provincial carbon emissions, showing a “U-shaped” nonlinear relationship. In the early stage of industrial cooperative clustering, production efficiency can be improved and carbon emissions reduced through sharing of resources, technological innovation and exchange of experience; in the middle and late stage of industrial cooperative clustering, the emission reduction effect lags behind the expansion of production capacity and the waste of resources brought about by industrial clustering, thus increasing carbon emissions. Cooperative industrial agglomeration not only has an impact on carbon emissions in the region, but also has a spillover effect on carbon emissions in other regions. This paper proposes to promote the transformation and upgrading of industrial structure, encourage the collaborative industrial agglomeration, strengthen the environmental regulation, force the enterprises to carry out technological innovation and pollution control, encourage the inter-regional economic cooperation, strengthen the data regulation and governance.