[en] Suggested is a model of diffractive hadron fragmentation in pomeron exchange processes to explain the production of high-energy pions and gamma-quanta in collisions of nucleons and pions of cosmic radiation at energy E₀approximately equal to 10¹³ eV. A mass spectrum of diffractive-excited nucleon states, multiplicities of π⁰-mesons and gamma-quanta, a cross section of the process of diffractive dissociation of incident proton as well as inelasticity coefficient are calculated. A threshold effect of gamma-quantum registering and anisotropy effect of angular distribution of decay products of nucleon isobars take into account. It is shown, that the frequency of high-energy π⁰-meson production and the fraction of E₀ primary energy, taken away by them, can be attributed to diffractive fragmentation of incident hadron. Anisotropy of angular distribution of decay products of diffractive-excited system insignificantly affects inelasticity coefficient value. Processes of diffractive fragmentation of incident pions and nucleons slightly differ one from another in their characteristics