Abstract: Disclosed is a preparation method for tricalcium silicate powder. The method includes the following steps: taking CaCO3 powder and SiO2 powder as raw materials for preparation, so as to obtain mixed powder having uniform components; pre-pressing the obtained mixed powder to make a blank; and performing sintering treatment on the obtained blank at a temperature of 1,200 DEG C-1,500 DEG C for 0.5 h-1.5 h, so as to obtain tricalcium silicate, where the sintering treatment is to perform mixed sintering by using auxiliary heating bodies and in cooperation with microwave treatment. According to the present disclosure, the tricalcium silicate is prepared through mixed sintering by using the auxiliary heating bodies and in cooperation with the microwave treatment, and a mixed heating mechanism enables a sample to be heated more easily at a low temperature, so that synthesis purity and efficiency are improved.