The effect of the addition of La³⁺ cations on the structural properties of Pt/WOх/ZrO2 catalysts and the characteristics of catalytic activity in the process of hydroisomerization of  n-heptane and benzene mixture was studied. The phase composition of the catalysts is represented by a solid solution of lanthanum cations in nanocrystalline zirconia of tetragonal modification with localization of lanthanum in the surface layers predominantly. The positive effect of La^{3 +} additives on the selectivity and yield of isomerized products was shown.