Abstract: Red-bed soft rock is a special kind of rock-soil,which has the characteristics of low strength,easy softening and disintegration in water. When it is directly used as engineering filler,it will cause many engineering geological problems such as foundation cracking,subsidence,collapse and so on. Therefore,in order to improve the disintegration of red-bed soft rock filler,we choose the soft rock filler excavated from red-bed slopes in Jintang County and Zhongjiang County of western Sichuan as research object. Then,using guar gum,lignin fiber and polypropylene fiber as modified materials,we carry out the disintegration experiment of remodeling red-bed soft rock filler in western Sichuan under the conditions of single and guar gum-lignin fiber and guar gum-polypropylene fiber composites. By comparing the disintegration macroscopic morphology,disintegration rate,disintegration velocity and final disintegration rate of Jintang and Zhongjiang in western Sichuan under different improvement conditions,we analyzed the improvement effect of disintegration resistance and revealing the mechanism of action from a microscopic perspective. The results show that guar gum has the best improvement effect when using one single material,and the best blending ratio is 1%. The improvement effect of polypropylene fiber is weaker,and its improvement effect is related to the length and blending. The polypropylene fiber length is 6 mm and the incorporation ratio is 0.8%. The improvement of using lignin fiber on the disintegration resistance of remodeling red-bed soft rock filler in western Sichuan is almost 0. Compared with single material,the composite improvement of guar gum-polypropylene fiber and guar gum-lignin fiber has a more significant effect on the disintegration resistance of remodeling red-bed soft rock filler in western Sichuan,and the improvement effect of guar gum-polypropylene fiber is the best. The research results will provide some reference for engineering construction and disaster prevention in Jintang,Zhongjiang and other red-bed soft rock areas.