Objective To investigate the correlation between cardiac polyps and gastroesophageal flap valve (GEFV). Methods The clinical, endoscopic and pathological data of 349 patients with cardiac polyps (the cardiac polyp group) visiting Affiliated Hospital of Yangzhou University from January 1, 2016 to December 31, 2021 were retrospectively collected, and the same number of non-cardiac polyp patients (the non-cardiac polyp group) were matched in the same period as control according to the propensity score. The clinical, endoscopic and pathological data of the two groups were compared. Results After matching with propensity score, there were 296 patients in each group, with no significant differences in smoking, acid reflux, heartburn, Helicobacter pylori infection, bile reflux, reflux esophagitis or pancreatitis between the two groups (P>0.05). Compared with the non-cardiac polyp group, the risk of cardiac polyps increased in GEFV Ⅱ patients (OR=3.046, 95%CI: 2.100-4.419, P<0.001) and GEFV Ⅲ patients (OR=4.202, 95%CI: 2.299-7.681, P<0.001). Compared with the non-cardiac polyp group, the risk of cardiac polyps increased in patients with GEFV abnormalities (OR=2.822, 95%CI: 1.615-4.931, P<0.001). GEFV abnormalities was associated with the cardiac polyp site (χ2=22.169, P=0.003) and was not significantly associated with cardiac polyp size, number, morphology, intestinal metaplasia of the surrounding mucosa or intraepithelial neoplasia (P>0.05). Conclusion The occurrence of cardiac polyps is related to GEFV, and the patients with GEFV abnormalities are more likely to develop cardiac polyps.