Dirac monopoles in the cosmic space are expected to be accelerated by cosmic magnetic fields and decelerated mainly by Hubble's recession of galaxies. The estimated average energy of cosmic monopoles, carrying the Dirac's elementary magnetic charge, is 1020.4±1eV with a rather sharp differential energy spectrum. The hypothesis that most of extensive air showers (EAS) over 1018eV are initiated by cosmic monopoles is not in conflict with any of previous experiments conducted in search for monopoles. Preliminary discussions about the structure of monopole initiated EAS's and about more extensive monopole experiments are also given.