Objective:To study the method of preparing ginkgolides sustained-release tablets and investigate its vitro release characteristics.Method:the release of ginkgolides A（GA） and ginkgolides B（GB） was used as indicators to evaluate and optimize the formulation.The effets of hydroxypropyl methyl cellulose（HPMC） type and amount

the lactose amount

low-substituted hydroxypropyl cellulose（L-HPC） amount and carboxymethyl starch sodium（CMS-Na） amount on release behavior in vitro were observed in single-factor testing method.Then the formula-tion was optimized by orthogonal design test to determine the best preparation technological conditions.Result:The sustained-release tablets which were taken once a day

were prepared with HPMCK4M as matrix

low-substituted hydroxypropyl cellulose as disintegrant

microcrystalline cellulose and lactose as fillers.The tablets released 30% in 2 h

60% in 6 h

and exceeding 90% in 12 h

meeting the requirements for sustained-release.Conclusion:Ginkgolides sustained-release tablets prepared in this method has good behavior of release characteristics.The shape of tablets and compressibility were good.The preparative technology is also simple with low producing cost.