  The structure of the extra high energy cosmic rays spectrum in view of the
decay of proton is considered. The time required for proton travel from the
source to the earth defines the limiting energy of proton. Protons with the
energies more than the limiting energy decay and do not give contribution in
the EHECRs spectrum. It is assumed that proton decays at the Planck scale.
Depending on the range of distances to the EHECRs sources, the range of the
limiting energies of proton is determined. This allows one to explain the
structure of the EHECRs spectrum.
