Objective To investigate the red blood cell distribution width (RDWC)and serum leptin (Leotin)levels in pa-tients with early onset coronary heart disease (CHD)and their correlation.Methods From January 2013 to April 2016,320 cases of hospitalized patients with chest pain,chest tightness in the cardiovascular department of the Gaoming District People's Hospital of Foshan City,Guangdong Province,were examined by coronary artery.Of which 240 cases were male under 55 years old,female under 65 years old patients with coronary heart disease (coronary heart disease group),another 80 cases of normal coronary angiography and treadmill negative males under 5 5 years old,female under 6 5 years old patients,as the con-trol group.Gensini score in patients with premature coronary heart disease was calculated according to the coronary artery imaging results,Comparison between the two groups of red blood cell distribution width and serum leptin levels were differ-ent,analysis of red blood cell distribution width and serum leptin levels and the correlation between the degree of coronary artery lesions.Results The red blood cell distribution width and the serum leptin level in patients with early onset coronary heart disease were (13.87 ± 0.31)% and (12.24 ± 2.21)μg/L,significantly higher than the control group (14.31 ± 0.22)% and (9.21±1.78)μg/L (t=11.742,11.116,P<0.001).And Gensini score was positively correlated with coro-nary artery (r=0.413,0.124,P=0.000,0.041).Correlation of red cell distribution width and serum leptin levels were posi-tively (r=0.107,P=0.008).The research object curve the predictive value of red cell distribution width in patients with premature coronary heart disease (ROC)analysis showed that the area of ROC curve of red cell distribution width (AUC) under 0.725(95%CI:0.679~0.764),red cell distribution width value 12.85%,the sensitivity was 68.1%,specificity was 65.4%.Conclusion In patients with premature coronary heart disease,the red blood cell distribution width and serum leptin levels were significantly increased,and was positively correlated with the degree of coronary artery disease,can be used as an independent predictor of premature coronary heart disease.