The precipitation titration method and colloid titration method are respectively used to determine the cationic degree of cationic polyacrylamides P (AM-DAC) samples that are self-prepared in the laboratory. And mathematical method is used to comparatively analyze the two methods. It is found that both precipitation titration and colloid titration can accurately measure cationic degree, but the colloid titration method is more stable and accurate than precipitation titration method. The influence of different factors on the colloid titration are also analyzed in experiments, and the experimental results show that the measured value of cationic degree is the closest to the theoretical value when the pH value is within the range of 1.75 to 2.2, the titration rate in the range of 0.01 mL/s to 0.05 mL/s, and the titrimetric solution concentration in the range of 1×10 -4 g/mL to 2×10 -4 g/mL.