The purpose of this research was to formulate and characterize solid dispersion (SD) of Simvastatin using Polyethylene glycol 4000 as the hydrophilic carrier and Methocel K15M as the release retardant by the solvent evaporation and co-grinding method. The influence of drug polymer ratio on drug release was studied by dissolution testing. Characterization was performed by Fourier Transform Infrared Spectroscopy (FTIR), and Ultraviolet Spectroscopy. Release data were examined kinetically. SD with 1:2 and 1:3 ratio of drug to polymer obtained by solvent evaporation and co-grinding were selected as the best candidates suitable for prolonged-release oral dosage form of Simvastatin.