OBJECTIVE: To prepare time-controlled matrine pellets by fluidized bed for colonic delivery. METHODS: Firstly, the pellets containing the drug were prepared by fluidized bed coater. Then, pellets were coated with the mixture of HPMC and ethylcellulose aqueous dispersion (Surelease) as the swelling and controlled release layer. Subsequently, the outer layer of the pellet was coated with Surelease as the time-controlled film. The release rates of coated pellets were investigated by dissolution test in vitro. Coating quality and the changing process of coated pellets in the dissolution media were evaluated by scanning electron microscope (SEM) and optical microscope (OM), respectively. RESULTS: The rapid release of matrine started by rupture of time-controlled layer. The thickness of two coating layers and the ratio of Surelease to HPMC could control the lag time of the coating pellets and the rate of release. In the optimized double-layer coated pellets, drug release was initiated after a lag time of 5 h and completed within 16 h by a nearly constant speed in a step changed pH media. CONCLUSION: The thickness of two coating layers and the ratio of Surelease to HPMC could control the lag time of the coating pellets and the rate of drug release. The approach utilized in the present study may be helpful to formulate other hydrophilic drugs with low molecule weight for preparation of time-controlled pellets for colonic delivery or delayed release.