The objective of this study is to evaluate the use of emulsified heavy oils to conduct the FCC reaction. The emulsified heavy oil was prepared by homogenizing. Properties of emulsified heavy oil, including interfacial tension, dynamic viscosity, droplet distribution, and stability, were determined. Emulsified heavy oils were made using two types of pulping black liquor, namely untreated and partially recycled alkali black liquor. Stabilized emulsified heavy oil was used in the FCC reaction to investigate the product distribution, and pure heavy oil was used as the control. If the black liquor infiltration capacity is 5 wt. %, the catalytic cracking conversion and selectivity of the emulsified heavy oil and pure heavy oil were appraised at a temperature of 450 degrees C using a fluid fixed bed. Compared with the pure heavy oil, the emulsified heavy oil had higher conversion and better selectivity towards the liquid products, and the liquid products yield of l-E-5 emulsion increases from 66.73 wt. % to 71.30 wt. %. Furthermore, the selectivity towards coke of emulsified heavy oil conversion is lower than that of the pure heavy oil, and the coke yield of l-E-5 emulsion decreases from 10.74 wt. % to 6.26 wt. %. The No. l black liquor is more suitable as a catalytic cracking black liquor fuel oil emulsifier than that of No. 2 black liquor. Additionally, the negative effect of the emulsified heavy oil on the catalysis is limited, and the useful life of the catalysis was extended.