The reaction order with respect to TiCl4 was investigated in the quasiliving polymerization of styrene using a 1-phenylethyl chloride/TiCl4/Bu2O initiating system in mixture of 1,2-dichloroethane and n-hexane (55:45 v/v) at -15degreesC. It was found out that the reactions order with respect to TiCl4 was closer to 1. A mechanistic scheme to explain the kinetic behavior of quasiliving styrene polymerization in 1-phenylethyl chloride/TiCl4/Bu2O is proposed.