Recently, the Eyring-modified two-suffix-margules (MTSM) model for calculating viscosities of ionic liquid mixtures was proposed by Atashrouz et al. (Atashrouz, S.; Zarghampour, M.; Abdolrahimi, S.; Pazuki, G.; Nasernejad, B. J. Chem. Eng. Data 2014, 59, 3691-3704). In this work, a simple modification of the Eyring-MTSM model was presented and applied to the viscosity calculation of binary mixtures of organic solvents. The accuracy of the modified model was assessed by comparing experimental viscosities at atmospheric pressure for 182 binary mixtures, and the overall average relative deviation (ARD) between the calculated results and literatures is 0.61%. In addition, the relationship between the parameters in the model and the boiling point of mixtures was established. Experimental viscosities containing 478 binary mixtures were used to evaluate the reliability of the relations, and good agreement was obtained between experimental and calculated values with ARD of 1.62%. Furthermore, the modified Eyring-MTSM model was extended to the viscosities of high pressures. The ARD is 1.61% for the high-pressure viscosities of 63 binary mixtures. The predictive ability of the model was also tested, and the model is suitable for the prediction of the homologous mixtures.