Provided is a slow-release tablet including cilostazol as a pharmacologically active component, which is efficacious in suppressing aggregation of blood platelets and promoting vascular relaxation by inhibiting phosphodiesterase types. The slow-release cilostazol tablet has an extended elution time so that the slow-release cilostazol tablet can be taken once daily for convenience of drug use, and minimizes the manifestation of headache which is one side effect caused when women, the elderly and children take conventional cilostazol preparations so that the convenience of drug use can be improved. Also, the slow-release cilostazol tablet exhibits a stable elution pattern with no variation in elution rate according to changes in pH in the stomach and intestines, as well as an effect of delaying the release of a drug, using a mixture of hydroxypropyl methylcellulose and a carbomer as a release-controlling polymer.