Background/Aims: Many studies have suggested that hyperplastic polyps (HPs) are associated with adenomas and even malignancy. We investigated whether or not HPs are associated with the presence of synchronous advanced colorectal neoplasms as a function of their size and location. Methods: A total of 2,482 asymptomatic patients who underwent screening colonoscopies were classified into the following two groups: cases with advanced neoplasms and controls without advanced neoplasms. The proximal colon was defined as all segments proximal to the splenic flexure. We defined diminutive HPs as <6 mm in diameter and non-diminutive HPs as ≧6 mm in diameter. Results: The median age of the patients was 51 years. 76.8% (n = 1,909) of the patients were males. 82 patients (3.3%) had at least one advanced neoplasm. Based on multivariate analysis, the independent risk factors for advanced neoplasms were old age (OR = 2.81), male gender (OR = 2.92), non-advanced adenomas (OR = 3.57), and non-diminutive HPs (OR = 4.75, p = 0.000). Having at least one non-diminutive HP in either the proximal or distal colon was associated with an increased risk of advanced neoplasm, with no statistically significant difference (proximal vs. distal colon, OR = 5.95 vs. 5.36). Conclusions: These results suggest that non-diminutive HPs are important markers of advanced colorectal neoplasms regardless of location.