Abstract: Objective To discuss the correlation of mean platelet volume(MPV) and left ventricular ejection fraction(LVEF),serum high-sensitivity C-reactive protein(hs-CRP) and Cardiac troponin I(cTnI) levels in elderly patients with acute myocardial infarction (AMI). Methods One hundredcases of elderly patients with AMI were selected as the research object and as the observation group.The levels of MPV,LVEF,hs-CRP, and cTnI were detected within 24 h after admission hospital.There were quartile grouped according to the levels of MPV,Q1 group (MPV≤11.22 fl),Q2 group(MPV is 11.23-13.52 fl),Q3 group(13.53-14.26 fl),Q4 group(MPV≥14.26 fl),and 25 cases in each group;50 cases healthy volunteers were selected as control group that according to the patients in the observation group,age and sex matched at the same period.Compared to the observation group and the control group differences of each index,and analyzed the correlation between the patients in the observation group MPV and LVEF and hs-CRP,cTnI level. Results ①The MPV,LVEF and serum hs-CRP,cTnI levels in the observation group were significantly higher than those in the control group the differences were statistical significance (t₁=19.142，t₂=31.411，t₃=102.362，t₄=61.234，P＜0.05);②There was statistical significance in the LVEF and serum hs-CRP,cTnI levels between the different MPV groups (P<0.05),and Q1 group,Q2 group,Q3 group,Q4 serum hs-CRP,cTnI levels sequentially increased,LVEF decreased;③The linear correlation analysis showed a negative correlation of patients MPV and LVEF in the observation group (r_LVEF=-0.362，P＜0.05),and the linear correlation analysis showed a positive correlation of serum hs-CRP,cTnI level(r_hs-CRP=0.448，r_cTnI=0.512，P＜0.05). Conclusion MPV levels were significantly higher in elderly patients with AMI,and LVEF,hs-CRP and cTnI will have a significant correlation,and presumably it will be used as the objective index to evaluate the condition of patients with AMI.