Metformin hydrochloride, a type 2 diabetes hypoglycemic agent, shows high solubility in water, resulting in rapid initial release and side effects. Therefore, it is necessary to reduce the side effects and to increase the convenience using sustained release. The metformin hydrochloride was designed as a sustained release tablet agent through the wet granulation of PEO 8000k and Carbomer 940 which is a sol at low pH and is a gel at high pH and prevents the corrosion of tablets. FTIR was used for the chemical changes in the process of wet granulation, and DSC and XRD were performed to confirm whether the granules were formed. Morphological characteristics were observed using a scanning electron microscope. In order to confirm that the formulation was properly designed, the dissolution rate was confirmed through in vitro dissolution behavior. These results confirm the possibility of using metformin and appropriate polymers as a sustained-release formulation.