OBJECTIVE： To establish a fluorescence identification method of the microscopic characteristics for Plantagin Semen and its adulterants， and to provide technical support for the market supervision and inspection of TCM decoction pieces. METHODS： Under visible and ultraviolet light， comparative study and identification of the Plantagin Semen （seeds of Platago asiatica L. and Platago depressa Willd.） and its adulterants as seeds of Platago major L.， fruits of Schizonepeta tenuifolia Briq.， seeds of Codonopsis pilosula （Franch.） Nannf， seeds （peeled） of Kochia scoparia （L.） Schrad.， fruits of Bupleurum chinense DC. were carried out by means of stereoscopic fluorescence microscopy from aspects of overall surface characteristics， umbilicus characteristics and section characteristics. RESULTS： Under visible light， the surface texture of Plantagin Semen was wavy stripe or fine wrinkle， while the adulterants were wavy stripe， longitudinal edge or texture was not obvious. The umbilicus of Plantagin Semen was located in the center of the ventral surface， while that of adulterants were located at one end except for P. major. In the section of Plantagin Semen， there were obvious direct embryos， in which the adulterants were small or circular embryos except for P. major. Under ultraviolet light， P. asiatica had obvious wavy stripes in surface， orange and light blue-green fluorescence； P. depressa had grid-shaped wrinkles and gray-blue and gray-brown fluorescence； the umbilical fluorescence of Plantagin Semen was strong， and the fluorescence of the adulterants was weak except for S. tenuifolia. There were obvious differences in fluorescence color， embryo size and distribution between the section of Plantagin Semen and adulterants. CONCLUSIONS： The stereoscopic fluorescence microscopy is effect and accurate for the identification of Plantagin Semen.