Adiponectin (ORQ4 vs. Q1 = 0.358, 95% CI 0.216–0.594, p < 0.0001; adjusted p = 0.0002) and the A/L ratio (ORQ4 vs. Q1 = 0.378, 95% CI 0.219–0.653, p = 0.0001; adjusted p = 0.0009) exhibit a significant inverse association with the risk of endometrial cancer. This evidence concerns the gene ADIPOQ and endometrial cancer.