A laboratory procedure is described for the separation and recovery of the constituents in NbCl5-NbOCl3mixtures. The method outlined is based on the difference in solubility in liquid nitrosyl chloride of the addition compounds formed by niobium(V) chloride and oxychloride with NOCl. Following isolation of the nitrosyl complexes, thermal decomposition leads to regeneration of the original chlorides. The procedure can be conveniently applied to several grams of mixture in any proportion and permits recovery in nearly quantitative yield.