Objective: Corin has been suggested to be associated with obesity by cell-and animal-based studies. However, the association has not yet been studied in populations. Here, the aim was to explore the association in a general population of China. Methods: This was a cross-sectional study. Data on demographic information, lifestyle risk factors, and personal medical history were collected; body mass index, waist circumference, and blood pressures were measured; and serum corin, blood lipids, and blood glucose were determined in 2498 participants aged above 30 years. Results: Log-transformed corin correlated to body mass index (r 5 0.197, P < 0.001) and waist circumference (r 5 0.289, P < 0.001). In the risk factor-adjusted analysis, compared with participants in the lowest quartile of serum corin, participants in the 4th quartile had significantly increased risk of prevalent overweight or obesity (OR 5 2.26, 95% CI: 1.67-3.04) and central obesity (OR 5 1.74, 95% CI: 1.30-2.34). ORs of overweight or obesity and central obesity positively and significantly increased with serum corin levels (P for trend < 0.001). Conclusions: Serum soluble corin was significantly and positively associated with obesity. Our findings suggested that serum soluble corin may be a marker or risk factor for obesity.