OBJECTIVE： To optimize the water extraction technology of Yinju jiedu oral liquid， and provide reference for the industrial production of the preparation. METHODS： According to the investigation of extraction time-extraction rate curves of chlorohenic acid of Yinju jiedu formula and extraction rate of chlorohenic acid in Lonicera japonica and other combined medicinal materials in the formula， decoction methods and time of L. japonica were determined. Using the comprehensive scores of linarin， harpagoside， （R， S）-epigoitrin， psoralen+angelicin contents and dry extraction yield as indexes， L9（34） orthogonal test was designed to detect the effects of adding water amount， decoction time times and optimize the extraction technology of the residues and other medicinal materials. Verification test was conducted. RESULTS： The optimal technology was L. japonica decocted first for 30 min with 8-fold water； the residues and other medicinal materials were decocted with 8-fold water for 3 times， 1 h each time； combining all the syrups. In verification test， the average contents of chlorohenic acid， linarin， harpagoside， （R， S）-epigoitrin， psoralen+angelicin were respectively 34.51， 10.31， 1.97， 0.21， 9.79 mg/g （RSD＝1.24％， 1.19％， 1.40％， 1.71％， 1.28％， n＝3）； average dry extraction yield was 25.4％ （RSD＝1.64％， n＝3）； average extraction rate of chlorohenic acid was 78.95％ （RSD＝1.24％， n＝3）. CONCLUSIONS： In the optimized water extraction technology， both the extraction rate of chlorohenic acid and contents of other ingredients are relatively high. The technology is stable and feasible.