(1) Objective: To investigate the effect of HIF1-α/NF-κB/MMP2 signaling pathways mediated by ALDH2 on chronic intermittent hypoxia induced myocardial injury in rats. (2) Methods: Thirty SD rats were randomly assigned to three groups (10 rats in each group): control group (CONTROL), chronic intermittent hypoxia group (CIH), and CIH + ALDH2 group. Rats in the CIH + ALDH2 group were established by an intraperitoneal injection of the ALDH2 activator, Alda-1 (20 mg/kg), once a day for three consecutive days. After three months, changes in ventricular function were determined by ultrasound. The expressions of HIF1-α, NF-κB, and MMP2 proteins were detected by protein blotting, and the concentration of 4-HNE in myocardial tissue was measured. (3) Results: Compared with the control group, echocardiography showed that rats in the CIH group had significantly reduced myocardial function, elevated protein levels of HIF1-α, NF-κB, and MMP2 in myocardial tissues, and increased the expression of 4-HNE in myocardial tissues (P<0.01); Compared with the CIH group, rats in the CIH + ALDH2 group showed significant improvement in myocardial function, decreased protein levels of HIF1-α, NF-κB, and MMP2 in myocardial tissue, and decreased the expression of 4-HNE in myocardial tissue (P<0.01). (4) Conclusion: Chronic intermittent hypoxia increases the expression of HIF1-α to damage the myocardium and affect cardiac function, and ALDH2 inhibits the expression of HIF1-α to protect the myocardium.