In the title complex, [Cu(C(3)H(2)N(3)O(2))(NO(3))(C(12)H(8)N(2))], the Cu(II) ion is coordinated by an N and an O atom from a bidentate 1H-1,2,4-triazole-3-carboxyl-ate (TRIA) ligand, two N atoms from a 1,10-phenanthroline (phen) ligand, and an O atom from a nitrate ligand in a slightly distorted square-pyramidal environment. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link mol-ecules into one-dimensional chains propagating along the b axis direction.