Solvothermal reaction of [Ni(tppz)2](NO3)2 with Ln(NO3)3 ⋅ 6H2O afforded a 3d–4f heterometallic coordination complexes [Ni(tppz)2][Ln(NO3)5] ((where tppz = 2,3,5,6-tetra(2-pyridyl) pyrazine and Ln(III) = Nd (1), Eu (2), Gd (3), Tb (4), Dy (5), Er (6)). The complexes were characterized by elemental analysis, infrared spectroscopy, single-crystal X-ray diffraction, and powder X-ray diffraction. Moreover, UV-Vis absorption properties of 1–6 and solid-state luminescence properties of 2 and 4 are also discussed.