To explore the combustion behaviors of the rubber raw materials under the melt flowing conditions, the results including the mass loss rate (MLR), gas phase temperature and pool fire area of natural rubber (NR), butadiene rubber (BR) and styrene-butadiene rubber (SBR) were measured via a designed laboratory experimental setup. The results show that for these three rubbers, the peaks of MLR and the gaseous phase temperature under the melt flowing condition are higher than those under the condition of restricting the melt flow. The burning time under the melt flowing condition is half of that under the non-flowing condition, which is ascribed to the pool fire area enlarged by flowing melt. The pool fire area is demonstrated to be linear with MLR, and at the same MLR, the order of the pool fire area is NR＞SBR＞BR. The order of peak gaseous phase temperature is BR＞NR＞SBR, which is related to the average effective heat of combustion, the peak of MLR and the pool fire area of rubbers.