The apparent molal volumes of selected metal nitrate salts, Al(NO3)(3), Fe(NO3)(3), and Mn(NO3)(2), in water have been assessed from the available density measurements of their aqueous solutions at 25 degrees C over a wide molality range. The values of ?V have been fitted to the Pitzer model using its volumetric contributions. The model parameters beta(0)V, beta(1)V, CfV, and V0 were determined for each aqueous electrolyte, over the composition range from 0 to about 3.5 mol.kg1 H2O. The new experimental data and parameters obtained will be useful to extend the present database of electrolyte solutions as well as its application areas, allowing management of many physical properties of aqueous solutions in a numerical way in various end-uses.