The near fine structure of absorption K-spectra of nitrogen and carbon atoms in solid potassium tetracyanonickelate K2Ni(CN)4 is studied by the method of quantum yield of extrinsic X-ray photoeffect by means of an RSM-500 X-ray spectrometer-monochromator and bremsstrahlung of an X-ray tube with a tungsten anode. Resonant features in the structure of spectra obtained and in the NiK-spectrum known from the literature are identified within the framework of the quasi-molecular approach with the use of comparative analysis of NK- and CK-spectra of the Ni(CN)42- and Fe(CN)64- complex anions and a free HCN molecule. As a result of the analysis carried out, all of the form resonances are related to transitions of core electrons to free molecular orbitals (MO) of a Ni(CN)42- complex; symmetry of these MO and their relative energy locations are determined, and regions of spatial localization are found for each resonance. It is found that the lower MO of the complex are orbitals formed of antibonding 2π orbitals of CN- ligands. The shortening of the interatomic distance J(C-N) found in going from Ni(CN)42- (1.16 Å) to Fe(CN)64- (1.09 Å) is explained by the assumed decrease in transfer of the 3dπ-electron density to antibonding 2π orbitals of CN- ligands.