The invention relates to a catalytic cracking process for reducing sulfur content in gasoline and the device thereof, which includes a fluidized bed reactor in addition of a heavy oil catalytic cracking riser, characterized in enhancing contact time of oil-gas with the catalyst, further desulfurizing and reducing olefin content and increasing octane number in gasoline; regenerating all recycling catalysts, quality of products being stable and easily operated, reducing sulfur of gasoline to a maximum limit; adding a cooling device so as to avoid coking when the catalyst contacts with oil-gas in high temperature and decrease of yield of light oil resulted by excessively high reaction temperature of gasoline upgrading, improving products distribution, being flexible to change catalyst-oil ratio and reaction temperature of catalytic cracking reaction. The invention also provides an easily operated process for FCC desulfurization with stronger desulfurizing ability, good selectivity of products and high light oil yield, which can realize 40-80% of FCC gasoline desulfurization. Furthermore, more than 80% of FCC gasoline desulfurization can be achieved if the process is applied in combination with some particular catalysts.