Abstract: Traditional Chinese medicine(TCM) as prescribed by Chinese traditional physicians is usually available as “decoction slices” which calls for a ready method for assesment of quantity or even genuineness. Three groups of TCM drugs (radix Rubiae, bulbus Fritillariae and rhizoma Dioscoreae) were selected by using powder X-ray diffraction analysis with complete absorption profile. Topological regularity and characteristic peaks of the absorption profile were obtained as fingerprint in X-ray diffraction diagrams of the pertinent medicinal materials. We have discovered the similarities of 3 radix Rubiae samples gathered from different localities and their differences with Rubia tinctorum , the similarities and differences between 7 species belonging to Fritillaria Genus, the similarities of 2 rhizoma Dioscoreae samples from different localities and their differences with 2 counterfeits. The result points to a promising prospect in achieving an objective assessment of genuineness at TCM drugs.