The positron annihilation lifetime spectra were measured as a function of the heating temperature for the ultrastable Y (USY) zeolites. The lifetime spectra were well resolved into five lifetime components, and the longer lifetimes τ3, τ4 and τ5 are assigned to ortho-positronium annihilating in the β-cage, super-cage and the second pore in USY zeolite, respectively. The interesting observation is that the annihilation rate λ5 (the reciprocal ofthe τ5) of the fifth component increases and its intensity I5 decreases with the increasing heating temperature. The result is interpreted in terms of the increase in proton and the reaction between the positronium and proton in USY zeolite after heated.