Myocardial ischemia/reperfusion injury (MIRI) is a major cause of acute cardiac injury that is associated with high morbidity and mortality, and for which specific treatments are lacking. In this study, we investigated the underlying molecular mechanism of miR-144-3p in the pathological process of MIRI. A mouse I/R injury model and H9c2 cardiomyocyte hypoxia/reoxygenation (H/R) model were used to simulate the ischemia/reperfusion process in vivo and in vitro, respectively, and the relative expression and regulatory effect of miR-144-3p were determined. The target of miR-144-3p was also verified by a luciferase reporter assay. We found that miR-144-3p was significantly downregulated in mouse myocardium subjected to I/R and cardiomyocytes subjected to H/R. Upregulation of miR-144-3p significantly attenuated MIRI in vivo and in vitro. A Ca2+-activated chloride channel—TMEM16A (ANO1)—was identified as a target gene of miR-144-3p through bioinformatic analysis. The interaction between miR-144-3p and the 3ʹ-untranslated region of ANO1 was confirmed with dual-luciferase reporter assay, RNA immunoprecipitation assay, real-time quantitative polymerase chain reaction, and western blot analysis. Moreover, by targeting ANO1, miR-144-3p inhibited the activation of NLRP3 inflammasome inflammatory signals in myocardial cells. Collectively, the present study provides a novel insight into the role of miR-144-3p in the inhibition of MIRI, suggesting that the miR-144-3p/ANO1 axis may be a putative therapeutic target in myocardial ischemia.