OBJECTIVE: To compared the similarity between Cordyceps Sinensis and Solid Fermentation of Cordyceps Militaris in chemical components by TLC. METHODS: The similarity in total constituents and different extract fractions were compared between Cordyceps Sinensis and Solid Fermentation of Cordyceps Militaris by TLC. RESULTS: Solid Fermentation of Cordyceps Militaris and Cordyceps Sinensis were basically similar in that their TLC spots occurred at the corresponding place except a slight difference in size. CONCLUSION: Cordyceps Sinensis and Solid Fermentation of Cordyceps Militaris have similar chemical constituents, which remains to be further studied.