Muddy water infiltration is a common phenomenon in the Loess Plateau.The difference between infiltration processes of muddy water at different initial soil water contents is significant.Taking clear water as the control,we investigated the infiltration characteristics and infiltration decline rates of muddy water at different initial soil water contents.The results showed that the initial(at the end of first minute) and final stable infiltration rates as well as the cumulative infiltration volumes decreased exponentially as the turbidity increased.Those relationships appeared less variable with an increase in turbidity.For the same time duration,the cumulative infiltration volumes were always the greatest with clear water,and increasingly smaller as suspended solid concentration increased.The results of this study may be helpful to study soil erosion mechanism.