By using Lanlian fluid catalytic cracked (FCC) gasoline as a feedstock, the effects of weight hour space velocity (WHSV) on the product distribution, light oil compound, off-gas, and liquefied petroleum gas were researched in a confined fluidized bed reactor. The equation of off-gas yield, liquefied petroleum gas yield, coke yield, and light oil yield with increasing WHSV were established in the experimental data. The experimental result showed that with increasing WHSV, coke, off-gas, and liquefied petroleum gas yield decreased gradually, and light oil yield increased piece by piece; the amount of olefin was enhanced step by step, that of aromatics dropped slowly, and that of saturated hydrocarbon did not change. However, olefin conversion and increasing ratio of aromatics presented a slowly decreasing trend and increasing ratio of saturated hydrocarbon showed no change; hydrogen yield was low and did not change; i-butane and propane decreased, but n-butane increased gradually; C03/C=3 and nC04/nC=4 values did not change, iC04/iC=4 variety had no order; C03/C=3, C04/C=4, and (C03 + C04)/(C=3 + C=4) values showed a decreasing trend.