Abstract:Seed surface is unclearly observed of contaminated small seeds collected from herbarium specimens.After being soaked in low concentration of commercial detergent (0.001%), shaken in the ultrasonic wave bath(33 kHz, 50W), and rinsed in series content of ethanol with weak shaking in ultrasonic wave bath, the treated seed surface becomes more clear than untreated ones under SEM. This method is easy to operate and obviouslyeffective.