Objective:To establish TLC fingerprint of active antibacterial fraction of Pilea aquarum.Method:The activity fraction of P.aquarum was confirmed by antibacterial activity assay,and then the TLC fingerprint of 10 batches of P.aquarum from Guizhou was analyzed comparatively.Result:The EtOAc extraction of P.aquarum is antibacterial activity.The TLC chromatograms of 10 bat ches were very similar,which had 8 spots and 8 corresponding peaks,but the intensity of each peak was different.Conclusion:The method is simple and stabilized,and can be used for the quality control of P.aquarum Dunn.