Life cycle assessment was used to investigate the environmental impacts associated with the production of slag-calcium sulfoaluminate cement. The main sources of global warming potential (GWP) and primary energy demand (PED) were identified through sensitivity analyses. The CO2 mitigation effect of slag-calcium sulfoaluminate cement relative to Portland cement was further analyzed. The results show that the clinker calcination stage has the highest contribution to GWP and the raw material extraction stage contributes the most to PED in the production of slag-calcium sulfoaluminate cement. Sensitivity analysis shows that the most important factors influencing GWP are limestone and coal contentand the most important factors influencing PED are coal and electricity. Compared with Portland cementslag-calcium sulfoaluminate cement shows a significantly lower GWP and a slightly lower PED. The deficiency on mechanical properties at high slag dosages may hinder the application of slag-calcium sulfoaluminate cement as an alternative to Portland cement.