Based on the phenomenon that the acetonitrile-water system can form phase separation in the presence of sugar, a sugaring-out assisted liquid/liquid extraction coupled with HPLC protocol was proposed for the determination of honokiol and magnolol in traditional Chinese herbal formula Huoxiang-Zhengqi oral liquid. Extraction conditions such as the type and concentration of sugaring-out agent, the volume of acetonitrile, pH value, temperature, and vortex time were investigated. Separation was performed on a Diamonsil C-18 column (150x4.6mm i.d., 5 mu M) with acetonitrile and 0.05% formic acid (60:40, v/v) as mobile phase. The column effluents were monitored at 254nm. The method showed good linearity for honokiol and magnolol in the range of 0.5-50.0 mu g center dot mL(-1), and the limits of detection were 13 and 24ng center dot mL(-1), respectively. RSD values for repeatability and reproducibility were less than 1.62% and 1.80%, respectively. The recoveries were in the range of 85.8-103.7%. Compared with the Chinese Pharmacopoeia method, the established method was simple, fast, and greatly reduced the consumption of toxic organic solvent. Statistical test showed that the analytical results for the determination of the same sample by the two methods had no significant difference.