The emulsion stabilizing potential of chitosans was compared in the presence of organic additives. The 4 types suspension of 0.1 wt% of chitosan flocculant were obtained by mixing of chitosan colloidal dispersion with three kinds of additives; sorbic acid, benzoic acid and dibutylhydroxytoluene (BHT). The viscosity of emulsion revealed the following order of stabilizing potentials; sorbic acid > benzoic acid > BHT. As a bio-adsorbent for the treatment of biomedical wastewater, the results were capable of adsorbing more than 30% of pure chitosan. The chitosan emulsions represented that the removal efficiency were increased by COD 59.2%, BOD 70.1%, Zn 77.1%, Cu 93.7%, E. coli 99.4%. As a result of this investigation, it is remarked that the high stabilizing potential of chitosan solution is explained by higher adsorption efficiency with organics, heavy metals and microorganism, and that the effectiveness of chitosan solution for coagulating biomedical wastewater suspension could be improved due to stabilization of the viscosity in the presence of organic additives.