The study was carried out to extract lectin from Ceratophyllum demersum algae. Solvent conditions, material/solvent ratio and extraction time are factors that directly affect the extraction process, which are investigated for selection and analysis. The study investigated the conditions including solvent type (PBS buffer, ethanol, NaCl, NaOH solution), solvent material ratio (1/5, 1/10, 1/15, 1/20, 1/25, w/v), and extraction time (2, 4, 6, 8, 10 hours). The efficiency of the extraction process was evaluated by the total protein content, determined through the BSA standard curve by UV-Vis spectroscopy, and the erythrocyte agglutination activity. In general, these factors all significantly affect the extraction efficiency, the best results obtained for the extraction process are NaOH solvent, the materials/solvent ratio 1/10 (w/v) in 6 hours.