The electroreduction behavior of HNO3 was examined in acetone at Cd, Zn, Sn, Cu, Cu-Hg, and Ni electrodes. The kinetic parameters of the process and the nature of the reduction products were determined. By IR-spectroscopic studies of the HNO3 solutions in acetone, the state of nitrogen(+5) in this medium was elucidated. A marked effect of solvent properties on the reduction products was demonstrated by an analysis of data obtained in parallel for HNO3 electroreduction in three solvents, viz., acetone, dimethylacetamide, and water, which differ in their basicities and dielectric properties.