Adding proper amount of flocculants and coagulants into water can settle algal flocculation and remove algal bloom. Water body in scene is much complex and there are many factors affecting the flocculation effects. It is beneficial to improve the treatment effect to monitor the algae flocculation process in situ. Microcysts aeruginosa was used as a sample in this work to form flocculant suspension by adding different concentrations of polyaluminium chloride and kaolin, and then the polarization parameters of the different flocs suspension were measured by polarized light scattering technique. The results show that the polarization parameters can be used to characterize the flocculation processes affected by the dosage of flocculants and coagulants, which shows the potential of the proposed polarized light scattering technique to describe the algal flocculation process. It is indicated that the method provides an in-situ non-contact, unmarked and rapid monitoring tool for algal flocculation process research, algal blooms governance and monitoring, contaminated water treatment, pharmaceutical development, etc.