This study analyzes the extraction conditions of enzyme-assisted polyethylene glycol (PEG)-200 extraction of chlorogenic acid from Chrysanthemum indicum. Single factor test and response surface method are used to optimize the extraction process by employing chlorogenic acid extraction rate as inspection index, with cellulase dosage, liquid-solid ratio, enzymolysis temperature and enzymolysis time as test factors. Under the optimized extraction condition, four mathematical models of chlorogenic acid extraction from Chrysanthemum indicum at different liquid-solid ratios are established. The results show that the optimal extraction condition are as follows: 0.8% cellulase, with a liquid-solid ratio of 20∶1(mL∶g), at 55 ℃enzymolysis temperature and of 2.5 hours enzymolysis time. This optimal condition brings up the extraction rate of chlorogenic acid from Chrysanthemum indicum to 3.92%. Slogistic1 model can simulate the mathematical model process and best describe the extraction process of chlorogenic acid from Chrysanthemum indicum.