BACKGROUND Colorectal polyps (CPs) are frequently occurring abnormal growths in the colorectum, and are a primary precursor of colorectal cancer (CRC). The triglyceride-glucose (TyG) index is a novel marker that assesses metabolic health and insulin resistance, and has been linked to gastrointestinal cancers. OBJECTIVE To investigate the potential association between the TyG index and CPs, as the relation between them has not been documented. METHODS A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan, Jiangsu Province, China, between January 2020 and December 2022 were included in this retrospective cross-sectional study. After excluding individuals who did not meet the eligibility criteria, descriptive statistics were used to compare characteristics between patients with and without CPs. Logistic regression analyses were conducted to determine the associations between the TyG index and the prevalence of CPs. The TyG index was calculated using the following formula: Ln [triglyceride (mg/dL) × glucose (mg/dL)/2]. The presence and types of CPs was determined based on data from colonoscopy reports and pathology reports. RESULTS A nonlinear relation between the TyG index and the prevalence of CPs was identified, and exhibited a curvilinear pattern with a cut-off point of 2.31. A significant association was observed before the turning point, with an odds ratio (95% confidence interval) of 1.70 (1.40, 2.06), P < 0.0001. However, the association between the TyG index and CPs was not significant after the cut-off point, with an odds ratio (95% confidence interval) of 0.57 (0.27, 1.23), P = 0.1521. CONCLUSIONS Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals, suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC.