The effect of modulus, mass fraction and temperature of sodium silicate solution(SS) on the rheological characteristics of SS and geopolymer slurry(GS) were analyzed by means of viscometer and rheometer. Meanwhile, the effect of SS modified by ultrasonic on the workability of GS was studied. The results show that the viscosity of SS for 2.2 modulus get the minimum value in ambient temperature(1825℃), but the effect of modulus on viscosity of SS is gradually weaker with the raise of temperature. When SS is in the true solution(highionized) zone(modulus<1.8), the difference of GS viscosity of different SS modulus is little, while in the water glass(SiO2polymerized) zone(modulus>2.2), the viscosity of GS increases sharply with the increase of modulus of SS. With increasing of the mass fraction of SS, both viscosity of GS and SS are all increased.The viscosity of GS gets the minimum value at 30℃ in different SS modulus. The SS modified by ultrasonic could improve the fluidity of GS and increase the compressive strength of geopolymer.