Abstract: Aiming at ethylbenzene and dehydrogenation of ethylbenzene to styrene, the principle models for alkylation reactor, tranalkylation rector, ethylbenzene rectify tower, dehydrogenation of ethylbenzene to styrene, and styrene rectify tower are made, respectively, which have only 2% error with the actual production process. These models are used for the optimization design of the system process. The practical operation results show that this optimized operation system can effectively reduce the energy consumption and provide a support for the optimization of other ethylbenzene and dehydrogenation of ethylbenzene to styrene.