The objective of present study is to improve the dissolution rate of Acyclovir a poorly water soluble drug by solid dispersion technique using a water soluble carrier, PEG-6000, urea, mannitol. The solid dispersions are prepared by physical method, co-grinding method and solvent evaporation method. The prepared solid dispersions showed an enhancement in dissolution rate and solubility compared to plain drug. In vitro release profiles of all SDs were comparatively evaluated and also studied against pure acyclovir. Faster dissolution was exhibited by solid dispersion containing 1:4 ratio of drug: PEG-6000. The increase in dissolution rate of the drug may be due to increase in wettability, hydrophilic nature of the carrier and due to reduction in drug crystallinity. The prepared solid dispersion was subjected for % practical yield, drug content, infrared (IR) spectroscopic, differential scanning calorimetry (DSC). FT‐IR spectra revealed no chemical incompatibility between drug and PEG-6000.Drug– polymer interaction was investigated using differential scanning calorimetry (DSC) studies. Key words: Solid dispersions, carriers, solubility enhancement, poorly soluble drugs, bioavailability