Viscosities of three binary liquid mixtures of water + 1,4-dioxane, water + dimethylsulphoxide, dimethylsulphoxide + 1, 4-dioxane and of corresponding ternary system were measured at 303.15 and 313.15 K over the whole range of mixture compositions. Experimental data were correlated by means of some models in literature (MCALLISTER, REDLICH KISTER and by means of new suggested model (NPTL/v)). The viscosity of the ternary system was predicted using parameters determined from binary data. Prediction was improved by ternary parameter determined from experimental data. Predicted viscosities agree well with the experimental measurements.