The chemical composition of the surface of the equiatomic alloy TiNi was studied using x-ray electron spectroscopy. It is shown that titanium nickelide shows a tendency toward titanium segregation at the free surface. After thermal action in vacuum and in air, the fraction of titanium atoms in the surface layer reaches 98% of the total content of titanium and nickel. Under heat treatment in air an oxidized layer forms at the surface whose main component is TiO₂.