For a study, researchers sought to conduct a meta-analysis to learn how lipid levels impact colorectal polyps. Investigators searched the databases of PubMed, Web of Science, EMBASE, and Cochrane Library for relevant papers released between 2000 and 2020. The included papers were used to determine the mean and standard deviation of the body mass index and serum lipid indices in the colorectal polyps groups and control groups. Combining weighted mean differences (WMDs) and 95% CI, they evaluated the size of the effect of blood lipid levels on colorectal polyps. The publication bias of the included studies was assessed using the Egger test. There were 63,979 controls, 19,464 cases, and 37 articles in all. There was no significant publication bias. The cases showed lower levels of high-density lipoprotein cholesterol than the controls (WMD: −2.589 mg/dL, 95% CI: −3.273, −1.906). While the levels of triglyceride (WMD: 16.933 mg/dL, 95% CI: 13.131, 20.736), total cholesterol (WMD: 5.561 mg/dL, 95% CI: 3.477, 7.645), low-density lipoprotein cholesterol (WMD: 3.109 mg/dL, 95% CI: 0.859, 5.359) and body mass index (WMD: 0.747 mg/dL, 95% CI: 0.588, 0.906) were higher in the cases. There was a relationship between colorectal polyps and obesity and higher serum lipid levels. Hyperlipidemia and obesity could both be risk factors for colorectal polyps.