[en] We adopt the intra-nuclear cascade model to study the energy spectra of the high-energy (p,α) reactions on heavy nuclei. We assume that a target nucleus is composed solely of α particles and treat the reaction as multi-scattering processes between that incident proton and the resident α particles. When applied to ²⁷Al, ⁵⁰Co, and ¹⁹⁷Au at incident energies between 120 and 200 MeV, our results show excellent agreement with recent experiments even though a little underestimation at the lower excitation energy region still exists. However, it is pointed out that for a proper description of the angular differential cross-sections, in addition to the α particles, it is necessary to restore the nucleon degrees of freedom in the target nucleus