The controlled-release tablets of sasanquasaponin (SQS)-casein were prepared by using SQS, casein and guar gum as the main drug and accessory materials respectively. The method of determination of SQS in the controlled-release tablets of SQS-casein, and the effects of release media on the release rate and IR spectra of the controlled-release tablets of SQS-casein were studied, respectively. The release rate curve of the controlled-release tablets of SQS-casein was fitted as zero order, one order and Higuchi equation. The recovery was 98.59% when the content of SQS in the controlled-release tablets of SQS-casein in phosphate buffer solution (pH 6.8) as release media was determined with chromogenic reaction of vanillin- sulfuric acid. The release rates are 23.80%, 51.26% and 94.77% at release times 3, 6 and 12　h, respectively in phosphate buffer solution (pH 6.8) as release media. The controlled-release tablets of SQS-casein release SQS by slowness and constant in 12　h. The chemical bonds are formed among SQS, casein and guar gum.