Abstract: The densities of the mixtures of N,N-Dimethylformamide (DMF) and water(w) have been measured at ten temperatures from 278.15 K to 318.15 K with the vibra-tingtube density meter(Anton Paar Model DMA602). Then the excess molal volumes V~E of solutions and apparent and partial molal volumes of DMF over the range of mole fraction 0-1 have been determined. Comparing these quantities as functions of mole fraction of mixtures with the standard entropies of transfer for NaCl from water to DMF-H_2O mixtures as function of mole fraction of mixed solvent we found out there is a correspondence between the V_(DMF) varied with x and the standard entropies of transfer of NaCl. Both have the extremes at x=0.075. Therefore the structure of solution have been discussed. It might be considered that monomeric DMF molecules have been trapped in a quasi-clathrate "cage" made up of 12 water molecules at x=0.075 forming the possible closest packing of particles.