The main products from the deoomposition of lauroyl peroxide(1) in benzene at 50℃ have been identified as doeicosane, undecane(undeoene), undeeyl dodecanoate, dodecanoic acid, undeoylbenzene ete. The molar percentage yields of doeicosane and undecyl dodecanoate were not affected by the initial concentration of 1 and. the addition of galvinoxyl(2) as scavenger, indicating that these were cage products. The yields of undevaae, dodecanoio acid and undeoylbenzene all varied to different extent with the change of initial concentration of 1 and, upon the addition of 2, the yield of undecane dropped significantly while undeoylbenzene practically vanished.