Aim This study was designed to investigate the correlation between serum galectin-3 （Gal-3） levels and coronary lesion in patients with acute myocardial infarction. Methods This study included 31 patients with acute myocardial infarction that were confirmed by coronary angiography. Thirty non-coronary heart disease subjects confirmed by coronary angiography were recruited as control group. General clinical data of all the subjects were collected, the concentration of serum Gal-3, monocyte chemotactic protein-1 （MCP-1） and plasma high-sensitive C-reactive protein （hs-CRP） were assayed. And the degree of coronary arterial lesion were calculated by Gensini cumulative index. Results The levels of serum Gal-3 were significantly higher in patients with acute myocardial infarction than the patients in control group （P<0.05）. Serum Gal-3 levels were correlated positively with hs-CRP, MCP-1 and Gensini score （all P<0.05）. Conclusion Serum Gal-3 can predict the degree of coronary lesions in patients with acute myocardial infarction.