The kinetics of the reaction of ethylmethylphenylcarbinol catalyzed by sulfuric acid in the presence of phenol and ethyl methyl ketone to give phenylbutenes and byproducts were considered. The experimental data were treated within a suitable model by using an optimization procedure. The kinetic parameters governing the steps of the process and their dependence on water and acid concentrations as well as on temperature were determined. The results were compared with those of the analogous reaction carried out on dimethylphenylcarbinol.