Gliclazide is an antihyperglycemic drug, classified under second generation of sulfonylureas and also used in the treatment of Diabetes Mellitus type II (NIDDM). Gliclazide is practically insoluble in water and is included in Biopharmaceutical Classification System (BCS) class II, which the compounds in this class have a high permeability and poor solubility. The objective of this study is to generate gliclazide nanosuspension in order to improve physicochemical properties. The nanosuspension was conducted with high pressure homogenizer (HPH) with the formulation of 10% gliclazide and 2% polyvinyl alcohol (PVA). The obtained nanosuspension was evaluated with particle size measurement, polydispersity index (PI) and zeta potential. The physical stability study includes change of organoleptic, particle size and PI, in period of 2 months. The nanocrystals were also characterized with Scanning Electron Microscope (SEM), Differential Scanning Calorinietry (DSC) and Powder X-ray Diffraction (PXRD). Finally solubility profile and dissolution was conducted using three media including 0.1N HCl pH of 1.2, aqueous media and phosphate buffer pH of 7.4. The particle size and PI of obtained nanosuspension were 280.0 rim and 0.416. The obtained zeta potential was —0.55 rnV. Physical stability showed good appearance but increase in particle size after one weak from 292.8 nm to 1301.1 nm and PI value from 0.205 to 0.423. In addition, thermogram of DSC showed slightly shift in melting point of gliclazide due to attributed by PVA, as well as slightly decrease of the crystallinity of nanocrystals, which is further supported by PXRD results too. The gliclazide nanocrystals increase the solubility in three media and showing significantly highest solubility in phosphate buffer pH 7.4. Increasing in dissolution rate and percent dissolved can be seen at 120 minutes in raw material and nanocrystals sequentially in all three media, where in acidic media (19.28 and 47.32%), aqueous media (16.39 and 32.58%) and basic media (49.43 and 60.16%). Formulation of gliclazide nanosuspension increased the solubility and enhances the dissolution rate in different media.