To determine the content of astragaloside IV in Xiao'er Weijining Mixture, TCL conditions were optimized by comparing various refined methods. And they were as follows: the underlayer of CHCl 3-CH 3OH-H 2O(65∶35∶10) below 10℃was developed at 15～18℃ and sprayed with 10%H 2SO 4-C 2H 5OH,the heating temperature was 105℃ for 3～5 min,and ?S=400 nm, ?R =700 nm.