New bio-composites were successfully synthesized from Enteromorpha compressa macro-alga (ECMA) and polyanilic matrix (PANI) through oxidative polymerization. To examine the ECMA effect on the PANI's characteristics, different weights (5, 10, 15, 20 and 50%) of ECMA powder were incorporated into the polymer matrix. The in situ polymerization of aniline was confirmed by FTIR and UV-Vis spectroscopies which lead to the formation PANI emeraldine base. The XRD analysis showed that the crystallinity of PANI becomes more conspicuous with addition of ECMA as evidenced by the increased peaks intensities. The electrical conductivity measured by the four-probe method averages 10(-2) S cm(-1). The results showed that ECMA powder has a high ability as reinforcing material in the polymer matrix. As application, PANI-20% ECMA presents the best efficiency for the removal of yellow quinoline from aqueous solutions with an uptake yield of 85%. The adsorption isotherm is well described by the Freundlich model with a capacity of 118.906 mg g(-1), and the experimental data were fitted with the pseudo-second-order kinetic models.