Belite–barium calcium sulfoaluminate (C2.75B1.25A3$) cement is a new type of belite-rich cement with great long-term mechanical performance and good durability. Its early-age mechanical property was found to be comparable to that of Grade 32.5 ordinary Portland cement. In order to further improve its early hydration activity, the effect of two known early-strength agents on the performance of the belite–barium calcium sulfoaluminate cement was investigated by means of XRD, pore structure and TGA. It was found that Na2SO4 and Ca(HCOO)2 can be used as an early-strength-enhancing agents for this type of cement with the best dosage of 0.5 and 2.0% by weight, respectively. Ca(HCOO)2 was preferable to this type of cement from the durability point of view.