Fluid Catalytic Cracking (FCC) is one of the processes applied world-wide for upgrading of heavy petroleum cuts by converting them into lighter products in the gasoline, light, and heavy cycle oil ranges. Catalytic cracking process was developed in the early stages of petroleum refining. It started by utilizing chemically treated natural clays as catalysts. In the early 1960s the introduction of zeolite containing catalysts, mainly the wide pore faujasite family (X-and Y-type) has significantly contributed to the yield as well as FCC process design consideration. The overall process performance is strongly dependent the catalyst characteristics. Therefore, FCC catalyst manufacturers and researchers are continuously searching for modified catalyst characteristics (improved thermal and hydrothermal stability, higher Activity and better selectivity for high barrel-octane gasoline production). This research activity resulted in this introduction of several FCC catalyses with enhanced performance to suit the steadily increasing emand for high quality refined FCC products.