Two complexes [PyH][Ni(Mnt)2] (I) and [QlH][Ni(Mnt)2] (II) (Mnt2– = maleonitriledithiolate, [PyH]+ = pyridinium, [QlH]+ = quinolinium) were synthesized and characterized by elemental analysis and IR spectra. ESR spectra of polycrystalline samples collected at room temperature are isotropic with g = 2.039 for Iand anisotropic with g z = 1.997, g y ≈ g x = 2.102 (g av = 2.068) for II. The magnetic susceptibility data of I and II have been measured in the temperature range of 2–300 K. The results obtained suggest the antiferromagnetic coupling interactions between neighboring Ni3+ ions for I and ferromagnetic coupling interactions for II, respectively. Based on the crystal structure analysis of I, the magnetic properties of two complexes were discussed.