[en] Highlights: • The co-pyrolysis of BA and EP improved the quality of bio-oil. • The concentration of C_2–C_4 hydrocarbons significantly increased with presence of EP. • Co-pyrolysis chars had higher HHVs compared to pyrolysis of EP alone. • The synergistic effect was the most significant at the blend of BA/EP (50/50). - Abstract: Enteromorpha prolifera, a green algae, has been spreading widely in China in recent years, resulting in a series of adverse impacts, such as the water eutrophication and the outbreak of green tides. Thus, it is necessary to develop an extensively available method to transfer marine biomass waste into high-value products. In this study, Co-pyrolysis of sugarcane bagasse and E. prolifera was carried out in a fixed-bed reactor. The positive effects between sugarcane bagasse and E. prolifera were evidenced, as the acidity and density of the bio-oils from co-pyrolysis decreased and calorific value increased with respect to that of the merely biomass pyrolysis. When the ratio of the two components was 50/50, the bio-oil got the highest yield of 56.12 wt% and the high heating value of the bio-oil was 26.4 MJ/kg, which were 11.48%, 2.47% higher than the theoretical values, respectively. The acidity and density of the co-pyrolysis bio-oil at 50/50 blends were 51.62 mgKOH/g and 1.1185 g/cm"3, which were 16.18%, 6.29% lower than the theoretical values, respectively. The analysis of bio-oil compositions showed that the bio-oil from co-pyrolysis of the blends could be a potential source of renewable fuel with lower content of acid, ketone, aldehyde, phenolic compounds and higher content of hydrocarbon, alcohol, ester compounds. In addition, the concentration of C_2–C_4 hydrocarbon gases produced through co-pyrolysis of the blends increased as the amount of E. prolifera increased in the blend. The co-pyrolysis chars had higher calorific values compared to that through pyrolysis of E. prolifera alone.