Aim To investigate the expression pattern of plasma exosome mRNA inAMI(acute myocardial infarction ) patients using NCCP(noncardiac chest pain)patients as control group, and determine the possible effects of differentially expressed mRNAs in AMI patitents. Methods Fifteen NCCP andAMI patients were enrolled from Beijing Chao-yang Hospital and Baotou Central Hospital. Exosomes and exosome RNA were extracted from the plasma of selected patients. High-throughput sequencing technology was used to detect the expression of mRNA(message RNA )profile in exosomes in the plasma of patients with AMI and NCCP. GO (gene ontology) and KEGG (kyoto encyclopedia of genes and genomes) were used to analyze differentially expressed mRNAs. Results The size of exosomes was between 30-200 nm. These exosomes express CD63(cluster of differentiation 63) and HSP70 (heat shock proteins 70), but not GAPDH (glyceraldehyde-3-phosphate dehydrogenase), conforming with the characteristics of exosomes. 64258 mRNAs were detected in the plasma exosomes of AMI patients and 64374 mRNAs were detected in the plasma exosomes of NCCP patients.Among these detected mRNAs, 1800 mRNAs were differentially expressed in AMI group (951 mRNAs were upregulated, and 849 mRNAs were down regulated). GO and KEGG analysis showed that these differentially expressed mRNA participated in the biological regulatory functions and pathways of AMI. Conclusion The mRNA expression pattern of plasma exosomes in patients with AMI was significantly different from that in the NCCP group. These differentially expressed exosome mRNAs may play important roles in the occurrence and development of AMI.