The interaction of thorium tetranitrate with some organic ligands, which were used before with thorium tetrachloride was investigated. The effect of the anionic part of the metal compo- und on the nature and composition of the formed complexes were discussed. Study of the infrared spectra measured över 400-650 cm-1 region and thermal analysis in the range 25-800° C were carried out. Conductivity measurementes for the soluble complexes were done.