Abstract: It was studied that the effect of addition of fly ash and silica fume on self-leveling concrete strength and fluidity; according to the experimental data obtained, the strength empirical equation of high stren gth self-leveling concrete was summarized; it was also analyzed that the later strength increasing rule of high strength self-leveling concrete with flyash an d silica fume; C90 high strength self-leveling concrete can be prepared. By gra de 42.5 ordinary Portland cement, medium sand, 5～25mm broken stone, water/ceme ntitious materials ratio 0.267～0.285, addition of 10% flyash and 10%～15% sil ica fume, or water/cementitious materials ratio 0.266,addition of 20% flyash and 1 5% silica fume, proper quantity of NF-2-6 retarding high effect water-reducin g agent.