Excess molar volumes(V_m^E) of constituent binary mixtures of n-decane, n-dodecane, 1-decanol and 1-dodecanol which are the products of liquid phase oxidation of n-paraffins, have been measured experimentally as a function of composition x from density measurements at 308.15K. The excess molar volumes of n-decane-n-dodecane system have negative deviation from the ideality while that of n-dodecance-1-decanol system have positive deviation. In the other system, excess molar volume exhibits inversion in sign. Experimental data were successfully correlated with Redlich-Kister polynomial.