OBJECTIVE： To optimize the extraction technology of caffeic acid in Laggera alata， and establish a method for its content determination. METHODS： The caffeic acid in L. alata was extracted by reflux extraction. Using extraction content as investigation index， orthogonal test was used to investigate the effects of ethanol volume fraction， material-liquid ratio and extraction time on caffeic acid， and the extraction technology conditions were optimized. HPLC was adopted to determine the content of caffeic acid in 10 batches of L. alata from different areas， using caffeic acid as reference substance， at wavelength of 320 nm. RESULTS： The optimized extraction technology conditions were as follows as ethanol volume fraction of 10％， material-liquid ratio of 1 ∶ 40 and extraction time of 3 h. Under the condition， verification test for caffeic acid was carried out， and the average content of caffeic acid in L. alata was 0.521 1 mg/g （RSD＝1.18％， n＝3）. The content of caffeic acid in 10 batches of L. alata from different areas ranged in 0.375 2-0.776 6 mg/g， and the content showed great differences. CONCLUSIONS： The content of caffeic acid in L. alata is related to area and harvest season. The caffeic acid extration by optimized technology shows good reproducibility； and the established method for content determination is stable and feasible.