The octane number was one of main quality indexes of gasoline.Improvement of gasoline octane number and produce high quality gasoline was an important task for refining industry.The research progress in the methods of improving octane number of FCC gasoline were reviewed,included optimizing operation conditions of catalytic cracking unit,adding gasoline octane number promoting agent and using new technologies.The research direction of methods of improving octane number of FCC gasoline was prospected.