To study the influence of CS and CPAM on the filtering performance of pulp mixed with AKD emulsion and the apparent smoothness of molded pulp products. CS and AKD or CPAM and AKD were added to the old corrugated cardboard pulp slurry and flat molded pulp samples were prepared. Compared to slurry supplemented with AKD emulsion only, both the drainage time and beating degree decreased to some extent after the addition of AKD following CS or CPAM addition, and with the increasing dosage of CS and CPAM, the frictional coefficient decreased at first and then increased, in other words, the apparent smoothness of the samples was first improved and then decreased. The HSCS-02 quaternary ammonium cationic corn starch led to better filtering performance of the pulp, and it also improved the apparent smoothness of the molded pulp products, with an optimal addition dosage of 3%. CPAM was a better filter aid agent than CS, and it improved the apparent smoothness of the molded pulp products to a higher degree as compared to CS, with an optimal addition dosage of 0.06%.