Objective: It was to investigate the content alteration of the tannins in cibot rhizome and its processed samples. Method: The casein method was used to determine the content of tannins. Results: The content of tannins decreased after the medicinal material was processed. Conclusion: Processing may decrease the content of tannins in cibot rhizome. The raw was better than the other processed samples if the tannins were used as active constituents.