Abstract: Slurry liquidity has an important influence for grout diffusion and migration. By conducting orthogonal liquidity test on viscosity-varying grouting materials with different pumping time, the influence of water cement ratio and the additive agent on the properties of slurry flow are analyzed. Flow degree of time variation characteristics of the viscosity time-varying slurry are investigated. The changes of the flow of the slurry machine rational are discussed considering the effects of the additive agent on slurry hydration and hardening. Slurry liquidity in the application of grouting in cataclastic rock is studied. The results show that while increasing the amount of water cement ratio, additive #1, additive #2, additive #3, the flow of the slurry augmented. Water cement ratio is the most significant influence factor of fluidity, followed by additive #2, additive #3, additive #1. For the main factors of the influence on slurry viscosity followed by additive #3, additive #1, water cement ratio and additive #2. Slurry fluidity change presents three-stage development: slow increase, fast increase, and stable state. When nearing slurry pump time, slurry flow has significant change respectively. Grouting application in cataclastic rock mass shows that the use of grouting slurry considering time-varying viscosity can reduce refilling time for the ordinary cement slurry, shorten the grouting time, save the grouting material.