OBJECTIVE： To optimize the excipient formulation of Mosapride citrate gastric floating sustained-release pellets.METHODS： Single factor test was used to investigate the effects of different floating assistants， adhesives and effervescent agents on floating rate of pellets within 8 h. The excipient formulation was optimized by orthogonal test with the amount of octadecanol， HPMC and sodium bicarbonate as factors using comprehensive score of 8 h floating rate， roundness and recovery rate as indexes. Validation test was also conducted. RESULTS： The optimal excipient formulation included the weight of octadecanol， HPMC and sodium bicarbonate were 13.0， 3.7 g， 3.4 g. The results of validation test showed that comprehensive indexes of the pellets prepared by excipient formulation were high， which were consistent with the orthogonal test results. CONCLUSIONS： The optimal excipient formulation is stable and reliable，and is suitable for the preparation of Mosapride citrate gastric floating sustained-release pellets.