The crystal morphology of the energetic material cyclotrimethylene trinitramine (also known as RDX) influenced by the solvent effect was investigated via molecular dynamics simulation. The modified attachment energy (MAE) model was established by incorporating the growth parameter-solvent term. The adsorption interface models were used to study the adsorption interactions between solvent and RDX surfaces. The RDX crystal morphology grown from the cyclohexanone (CYC) solvent as a case investigation was calculated by the MAE model. The calculation results indicated that, due to the effect of CYC solvent, (210) and (111) faces had the greatest morphological importance on the final RDX crystal, while the morphological importance of (020), (002), and (200) faces were reduced. The predicted RDX morphology was in reasonable agreement with the observed experiment result.