We report the jet-cooled isomeric chloro-p-xylyl radicals in a corona-excited supersonic expansion (CESE), and its vibronic spectrum was recorded with a long-path monochromator. By the precursor 2-chloro-p-xylene, we identified the two isomeric benzyl-type radicals, 2-chloro-p-xylyl and 3-chloro-p-xylyl radicals in the corona discharge. The vibronic emission spectrum of the chloro-p-xylyl radicals corresponded to the D-1 -> D-0 electronic transition and determined the electronic transition energy depending on the constitutional isomers.