In order to solve the problem of large-scale leveling on the ground, a cement-based self-leveling mortar is prepared by using cement, silica sand powder, silica fume and other additives, and the effects of aggregate size, cement sand ratio, cellulose ether, redispersible latex powder, silica fume and other dosages on the performance of self-leveling mortar are studied. The results show that the self-leveling mortar prepared with aggregate size ?1.18mm , cement sand ratio of 1.0:1.2, cellulose ether mass fraction of 0.03% , redispersible latex powder mass fraction of 1.0% , silica fume mass fraction of 5% , and water-glue ratio of 0.35 has an initial fluidity and 20 min fluidity of more than 140mm , and the 24h compressive and flexural strengths are 9.2 and 3.5MPa , respectively, and the 28 d compressive and flexural strengths are 34.4 and 6.4MPa , respectively, which meet the technical requirements of "Cement-based Self-leveling Mortar for the Ground" (JC/T 985-2017).