Through in vitro hypoxia-reoxygenation (H/R) model of HL-1 cardiomyocytes and in vivo myocardial ischemia-reperfusion (I/R) model of C57BL/6 mice, this study systematically explored the role and molecular mechanism of triggering receptor expressed on myeloid cells-1 (TREM1) in MIRI. This evidence concerns the gene TREM1 and myocardial ischemia.