Crystal structures of neodymium (Ⅲ) and dysprosium (Ⅲ) nitrate complexes with the new ligand N, N'-dimethyl-N, N'-diphenyladipamide (mpaa) has been determined. Both complexes are triclinic with space group Pi ,formula [C22H30N5NdO12S]2 1 [C42H54N7DyO14S 2]Mr = 1465.62[1075.48], a = 8.541(1)[9.711(2)], b = 11.915(1)[16.017(3)], c = 15.906(1)[16.686(3)] A,α =107.22(1)[109.600(1)],β = 98.12(1)[92.50(1)], γ = 99.78(1) [96.22(1)]° ,μ=0.71073cn-1; R=0.0261 [0.0364], wR=0.0611 [0.0857] reflections with I＞2 σ (Ⅰ). Complex (1)is dinuclear, in which two Nd(Ⅲ) ions are double-bridged by two mpaa ligands. And Dy(mpaa)2(dmso)(NO3)3 (2) (dmso= dimethylsulfoxide) is a mononuclear complex, in which one of the two C=O groups in MPAA is uncoordinated. In the two above complexes, each Ln(Ⅲ)ion is nine-coordinated including three bidenate nitrates, one dmso molecule and two carbonyl oxygens from two different mpaa ligands. Neutral monodentate dmso enters the coordination in diamides of the type (R1R2NCO)2(CH2)n was increased, the ligand prefers to act as a bridging reagent rather than a chelate.