A disclosed comprehensive processing method for squeezing sewage generated in a process of extracting xanthophyll from tagetes erecta comprises the following steps: performing preliminary precipitation; filtering the upper-layer liquid, adding aerobic activated sludge into the filtrate and aerating for 8-10 days; performing precipitation on the aerated upper-layer liquid; adding anaerobic activated sludge into the upper-layer liquid subjected to precipitation and performing anaerobic fermentation for 8-20 days, and collecting generated biogas; performing precipitation on the supernatant subjected to anaerobic fermentation; filtering the upper-layer liquid subjected to precipitation, and performing decolouring processing; and enabling a clear liquid subjected to decolouring to flow out and storing in constructed wetland. Through precipitation, filtering, aeration, anaerobic fermentation, decolouring and constructed-wetland storage for comprehensively processing squeezing sewage generated in the process of extracting xanthophyll from tagetes erecta, the comprehensive processing method is low in cost, reasonable in economy and small in consumption, is capable of substantially reducing COD of squeezing sewage and purifying water quality, obtaining biogas energy source, and finally enabling wastewater to reach the standard by combining constructed-wetland ecological processing, helps to beautify environment, is high in automation degree and helps to reduce labor intensity.