In this study, the pre-equilibrium and equilibrium calculations of cross-sections of Y-89(p, xn), Zr-90(p, xn) and Mo-94(p, xn) reactions, which were used for the production of Zr-89, Nb-90 and Tc-94 positron-emitting radioisotopes, have been investigated. Pre-equilibrium calculations have been performed at different proton incident energies by using the hybrid, geometry-dependent-hybrid and full exciton models. The Weisskopf-Ewing model is used for calculating the equilibrium effects at the same incident energies. The calculated results have been discussed and compared with the experimental results.