Abstract: In order to study flood recession in karst watershed,flood recession in Huangzhou River Basin of Guizhou province was simulated by exponential model formula and baseflow separation method.The results showed that:(1) There was a correlation between total flow variation and baseflow variation in flood process of Huangzhou River Basin,and the flood recession was effected by rainfall duration,flow size and lithologic characteristics of the basin.(2) Recession rate of surface runoff was faster than that of underground runoff,large number of karst pores and cracks in the basin accelerated the drainage of underground runoff.(3) Initial recession flow was between 11.99 m3/s and 381.81 m3/s,and recession coefficient ranged from 0.033 to 0.084.The larger the recession coefficient was,the shorter the duration of rainstorm and flood was,and vice versa.(4) Exponential model for flood recession could simulate the flood regression in Huangzhou River Basin.