Gliclazide is a second-generation sulfonylurea class of oral antihyperglycemic compounds used for the treatment of type II diabetes mellitus (NIDDM or Non-Insulin Dependent Diabetes Mellitus). Gliclazide tablets on the market can be divided into generic and branded drugs. Differences in additives and production processes can cause differences in the quality of the gliclazide tablets produced, one of which is the kinetics and mechanism of drug release. This study aimed to determine the release kinetics of generic gliclazide tablets and branded gliclazide tablets in vitro. Samples were selected based on the products on the market, namely branded gliclazide tablets and generic gliclazide tablets (1 and 2). The gliclazide tablets used were conventional gliclazide tablets with a dose of 80 mg. The results of the physical evaluation include organoleptic, uniformity of weight, uniformity of size, hardness, brittleness, disintegration time showing the results according to the specified requirements. The kinetics and mechanism of drug release were analyzed by the Ddsolver program through different models, namely Order 0, Order 1, Higuchi, Hixson-crowell, Hopfenberg, Korsmeyer-peppas, Weibull, and Baker-lonsdale. The release model analysis uses 2 criteria: 1). Statistical parameters: R2 Adjusted, Akaike information criterion (AIC), Mean square error (MSE) and WSS (Weighted sum of squares); 2). Visual goodness of fit (GOF). The results of the evaluation of the dissolution data with the help of the DDSolver program showed that the release of branded and generic gliclazide tablets followed the order of release of Order one. The mechanism showing the branded gliclazide tablets and generic gliclazide tablets 1&2 is the erosion mechanism in the Hixson-Crowell equation.