Collagen is one of the predominant proteins found in all multicellular animals. In this paper, the performance of the ultrafiltration process (UF) for concentrating the collagen protein was studied by performing batch experiments using a membrane module with an effective area of 28 cm(2)and equipped with a regenerated cellulose membrane with a molecular weight cut-off of 5 kDa. The feed solution consisted of aqueous solutions of bovine collagen hydrolysate with a molecular weight of 10 kDa. The effects of feed concentration (1%, 2%, 3%, 4%, and 5%) on the performance were determined. The optimum operating conditions were: a transmembrane pressure of 5 bar and a temperature of 25 degrees C. The results showed that the permeability decreases with the increase of the volumetric concentration factor (VCF) for all five concentrated solutions of collagen tested. Also, the rejection of proteins increases with the increase in the concentration of the collagen solutions. The study confirms that the clogging phenomenon was dependent on the increase of concentration. Further, a mathematical modeling of fouling mechanism was analyzed based on Hermia's model. The concentration of the collagen solutions was also highlighted by viscosity measurements.