The influence of rapid transformation of 3 age Pieris rapae L. by the ethanol extract of different parts of Pulsatilla chinensis（Bunge） Regel. was studied in the paper. The results showed that the regression equation of 48 h and 72 h were Y1=67.702+0.319X1 and Y2=80.668+0.394X1. The ethanol extract of root have promotion role to rapid transformation of Pieris rapae L., and when the concentration was 37.5 mg/mL the rate of transformation was the highest, 99.7%.