Objective: To explore the feasibility of quality control index of processed alisma pieces. Method: The content of 24-acetyl alisol A and 23-acetyl alisol B in processed alisma pieces was determined by high performance liquid chromatography; appearance information of processed pieces was gotten by cameras and Adobe Photoshop software, to evaluate the shade diferential of different origin. Result: The total amount of 24-acetyl alisol A and 23-acetyl alisol B in every processed alisma were more than 0.08%. Color uniformity of processed alisma was between 10 to 2.5, and the processed alisma chromatic diferential was in the 2-8 chromatic units. Conclution: The quality control indicators to reflect the intrinsic quality of processed Alisma Pieces can be used for quality control of traditional Chinese medicine alisma.