The effect of decationized forms of NaY, NaZSM-5 zeolites on the properties of Pt-Re/Al2O3 catalyst at n-octane reforming has been shown. The promoted additives increase the isomerization activity of catalysts. Activity and selectivity of the modified catalysts depend on both degree of ion exchange and (Si/Al) ratio of zeolites. One hundred percent selectivity of i-octane formation is reached at the introduction of promoter additive (element of the V group).