Abstract: In the present study，silymarin sustained-release tablets were developed to delay the drug release，reduce dosing frequency and improve patient compliance.Due to aqueous insolubility of silymarin，the solid dispersion was prepared by the solvent method using PVP K30 as the hydrophilic carrier matrix.Direct compression method was used to prepare silymarin sustained-release tablets.The influence of matrix forming agents on silymarin release was investigated based on in vitro release and the formulation was optimized.The optimal formulation was obtained using compritol 888 ATO as the sustained-release matrix，microcrystalline cellulose as the filler and magnesium stearate as the lubricant.The prepared tablets have shown an ideal sustained-release of silymarin with good reproducibility and compressibility.