Abstract: In this paper the reaction of Nd metal vapor produced at high temperture under Va-cuum below 10^-4 mmHg with chlorobezene at-196℃ to give phenyl neodymium chloride hasbeen preliminary investigated.The composition of the product was identified as C₆H₅NdClby chemical analysis. The compound is a black crystalline, insoluble in organic solvents,stable at room temperatue, extremely air-moisture sensitive, and pyrophoric in air. The complex combined with Al(i-Bu)₂H is able to polymerize diene to polybutadienewith cis-1, 4 contents of 94.4%, trans-1, 4 4.7%, 1.2-0.9% and polyisoprene with cis-1, 4contents of 94.4% and 3,4-of 5.6%.