Objective To observe the expression of obesity-related protein (FTO) in non-small cell lung cancer (NSCLC) and its effect on NSCLC angiogenesis and explore the mechanism.Methods RT-qPCR was used to detect the expression level of FTO in 45 NSCLC tissues and adjacent tissues. Western blotting was used to observe the protein expression of FTO in the tissues. They were divided into adjacent and NSCLC groups. ShRNA was used to knock down FTO in vitro, and the cells were divided into sh-NC and sh-FTO groups. RT-qPCR was used to detect the expression level of FTO in 5 lung cancer cell lines and airway epithelial cells, and the protein expression of FTO in the cells was observed by western blotting. Cell counting kit 8 (CCK-8) and tumor-bearing experiment were used to detect the effects of FTO on the proliferation of NSCLC cells in vitro and in vivo. The tube formation experiment observes the length of the tube formation.Results The mRNA and protein expression of FTO in 45 cases of NSCLC tissues was higher than that of adjacent tissues (all P＜0.05). The expression of FTO in lung cancer cells in vitro was also higher than that of airway epithelial cells (all P＜0.05). Knockdown of FTO (sh-FTO) inhibited the proliferation of NSCLC cells in vivo and in vitro (both P＜0.05), and knockdown of FTO inhibited the tubule formation length of NSCLC cells (P＜0.05).Conclusion The expression of FTO in NSCLC tissue is higher than that in adjacent tissues. Low expression of FTO affects the occurrence and development of NSCLC by inhibiting proliferation and angiogenesis.