Excess volumes have been measured by means of a continuous-dilution dilatometer for (glutaric dinitrile + benzene or toluene or o-xylene or styrene) and for (adipic dinitrile + benzene or toluene or o-xylene or m-xylene or p-xylene or ethylbenzene or styrene) at T = 298.15 K. V(E) values are negative over the entire range of composition for all mixtures. Absolute value of V(m, min)E and Absolute value of V(m)E(x = 0.5) values for {1-x)NC(CH2)4CN + xC6H4R’R"} are larger than for {(1-x)NC(CH2)3CN + XC6H4R’R"}. The results are discussed by comparison with those for binary mixtures of an aliphatic mononitrile, containing one -CN group, and an aromatic hydrocarbon.