Triisopropanolamine (TIPA) is one of the commonly used components of cementgrinding aids. At present, TIPA has studied the strength and hydration properties of Portland cement and Portland cement containing fine limestone particles. However, TIPA's research on the hydration mechanism of limestone Portland cement and the influence on the microstructure of Portland cement and limestone Portland cement hardened slurry is not comprehensive enough. Through TIPA study on the strength of Portland cement and limestone Portland cement, it was found that TIPA did not significantly increase the early strength of cement, but TIPA gradually showed its enhancement effect with the extension of age. The enhancement of the late strength of limestone Portland cement by TIPA is more significant than that of Portland cement.