New cyanamidonitrate complexes of the type [Ni(NO2NCN)2L4], where L = pyrazole (pz), 3(5)-methylpyrazole (mpz), 3,5-dimethylpyrazole (dmpz), 3,4,5-trimethylpyrazole (tmpz), indazole (benzopyrazole; inz), 4-bromopyrazole (Br-pz) and 4-iodopyrazole (I-pz) have been isolated and characterized by i.r. and electronic spectroscopy. The crystal structure of [Ni(NO2NCN)2(pz)4] was solved by X-ray crystallography. The NiII environment is practically octahedral, composed of four tertiary nitrogens from pyrazole ligands and two nitrile nitrogens from cyanamidonitrate groups. According to the spectral results similar molecular structures can be attributed to all remaining complexes. The i.r. spectra exhibit changes in the cyanamidonitrate vibrations caused by coordination of this group. The electronic spectra are in agreement with the practically octahedral NiII environment.