A 2,2'-[2,3-naphthylenebis(oxy)]-bis(N,N-diisopropyl(acetamide)) ligand (L) and its Gd(III) complex have been prepared and characterized. The crystal and molecular structure of the complex was determined by single-crystal X-ray diffraction. The interactions of complex with calf thymus DNA were investigated by UV-vis, fluorescence and viscosity measurements. Experimental results indicated that the complex can bind to DNA by intercalation modes. Its intrinsic binding constant is 1.03 x 10(6) M(-1).