This is a review article on the Galactic extragalactic cosmic rays with a particular emphasis on contributions made by Japanese group. Recent experiments by Japanese laboratories on air showers as well as high energy interactions have been disclosing a change in chemical composition, directional distribution and other properties of cosmic rays as their energy increases. While, the collaboration in theoretical studies on the evolution of galaxies, which are reviewed in this and accompanied issues, have made possible to make an estimate on the cosmic ray production rate from the extragalactic sources, active galaxies. It is shown from the above two pieces of information that the extragalactic component is dominating in the energy region over ∼1017 eV. Our theoretical study on structure and evolution of the Galaxy makes one possible to understand the interrelationship between the cosmic rays and other materials in the Galaxy. Relations between the halo and the cosmic rays are re-examined and the conclusions show that one should be free from the current hypothesis which assumes the Galaxy as a simple uniform reservoir of cosmic rays. Several experimental methods are suggested to examine new possibility. Analyses are made on effects of possible local cosmic ray sources near the solar system. Our estimation will be useful for designing further experiments, since recent progress in research on extensive air showers as well as the secular variation of cosmic ray flux are suggesting existence of this effect.