In the monomeric dinuclear title complex, [CuSm(C(20)H(22)N(2)O(4))(NO(3))(3)], the four-coordinate Cu(II) ion has a square-planar geometry involving two O atoms and two N atoms of the deprotonated Schiff base ligand. The Sm(III) ion is ten-coordinate, chelated by four O donor atoms of the Schiff base and two O atoms each from three bidentate nitrate groups, one of which is disordered over two sites in a 0.55 (7):0.45 (7) ratio.