The native asphalts in Oregon have never been thoroughly described, their character determined, or their significance discussed. This paper presents a complete list of all known occurrences, some of recent discovery, and tenders for the first time analyses and determinations of their character. They are found to be mixtures of uintahite, manjak, and wurtzilite, or pure uintahites and grahamites. These native asphalts have been derived probably from deep-seated Cretaceous rocks, which once possessed reservoirs of petroleum. The petroleum was brought to the surface by dynamic movements at the close of the Eocene or in the early Oligocene period. Their method of emplacement shows no influence of thermal metamorphism. Some of the Oregon occurrences are similar to those found n other localities which have since developed into important oil fields. Other Oregon occurrences are unique, and neither in Oregon nor elsewhere have they heretofore been described. The whole discussion has an important bearing on the possibilities of petroleum in Oregon.