RESUMEN
OBJECTIVE:To study the quality standard of root of Urtica dioica and investigate the sample’s content in different harvest periods. METHODS:TLC was conducted to identify the scopoletin in the root of U. dioica with the developing agent of hexane-dichloromethane- ethyl acetate- formic acid (6∶10∶7∶1.2,V/V/V/V);alcohol-hot dipping was used to determine the con-tent;and the root of U. dioica in different harvest periods were comparatively researched. RESULTS:The lactone thin-layer chro-matogram feature was obvious,alcohol-hot dipping showed the contents of root of u. dioica was relatively high(RSD≤1%),the ex-tract content of root of U. dioica was the highest from late fall to early spring,and the stage was suitable excavation period. CON-CLUSIONS:The established quality standard can be used for accurately qualitative and quantitative,and studying different harvest periods is conducive to effectively control the quality of root of U. dioica.