The jet-cooled m-chlorobenzyl radical has been generated for the first time from m-chlorotoluene with a large amount of carrier gas He in a corona excited supersonic expansion using a pinhole-type glass nozzle. The visible vibronic emission spectrum of the m-chlorobenzyl radical in the transition of D-1 --> D-0 has been recorded with a long path monochromator. The spectrum. has been analyzed to obtain the accurate:electronic transition and vibrational mode frequencies in the ground electronic state by comparing with those of an ab initio calculation and of m-chlorotoluene.