On diphenylamine-carbon tetrabromide system, various reaction intermediates were observed in their n -hexane, benzene and methanol solutions. 1) diphenylamine cation radical which has a absorptionmaximum at 640, 650 and 670 nm in n -hexane, benzene and methanol respectively. 2) triphenylmethane type radical which has absorption maximum at 655 and 645 nm in n -hexane and benzene. 3) other intermediates. 3-1) diphenylmethane type radical which has absorption maximum at about 450 nm, 3-2) phenylmethane type radical which absorbs near ultraviolet light around 350 nm, 3-3) bromine radical which has a absorption maximum at about 460 nm, 3-4) etc.