Abstract: This study aimed to optimize the extraction and purification processes for selenium-enriched Morchella esculenta (L.) Pers. (also known as Morchella) polysaccharides (Se-MPS) and to evaluate their anti-tumor activities and mechanisms. The extraction process was optimized using single-factor and response surface methodology. The crude polysaccharides were purified through column chromatography and their chemical composition was analyzed. The anti-tumor activity of Se-MPS was evaluated using HepG2 cells through a series of assays, including CCK-8, colony formation, scratching, and Transwell assays. The potential anti-tumor mechanisms of Se-MPS were assessed using RT-qPCR, Western blot, and immunofluorescence methods. Experimental results from single-factor and response surface methodology revealed that the optimal extraction conditions for selenium-enriched Morchella crude polysaccharides were: An extraction time of 2.5 h, a liquid-to-material ratio of 45:1 (mL/g), and an extraction temperature of 82 ℃, yielding a crude polysaccharides yield of 7.95%. After purification, the total sugar content of Se-MPS reached 95.86%, with a selenium concentration of 76.07±0.32 mg/g. Furthermore, Se-MPS significantly reduced colony formation efficiency, cell migration rate, and the number of invasive cells in HepG2 cells (P<0.05). Meanwhile, Se-MPS inhibited the PI3K/Akt signaling pathway, down-regulated mRNA expression of glucose transporter 2 (GLUT2), and reduced glucose uptake in cells. The results indicated that optimizing extraction time, liquid-to-material ratio, and extraction temperature could improve the yield of selenium-enriched Morchella crude polysaccharides. Additionally, Se-MPS exhibited strong anti-tumor activity by regulating the PI3K/Akt pathway. This study provides evidence of the anti-tumor activities of Se-MPS and offers insights for the development of related functional foods.