BACKGROUND: To assess the effectiveness of Shugan Jieyu capsules on peripheral blood miR-124, miR-132, and brain-derived neurotrophic factor (BDNF) levels in patients with mild to moderate depression following coronary artery intervention [percutaneous coronary intervention (PCI)] for coronary heart disease. AIM: To evaluate the therapeutic efficacy of Shugan Jieyu capsules and their effects on the peripheral blood levels of miR-124, miR-132, and BDNF in patients with mild to moderate depression following PCI for coronary heart disease. METHODS: Patients with mild-to-moderate depression of the liver-qi stagnation type after PCI for coronary heart disease at the 305 Hospital of the People's Liberation Army were enrolled from June 2022 to November 2023 and randomly assigned to two groups: Experimental (treated with Shugan Jieyu capsules) and control (treated with escitalopram oxalate tablets). This study compared the antidepressant effects of these treatments using 17-item Hamilton Rating Scale for Depression (HAMD-17) scores, metabolic equivalents, low-density lipoprotein cholesterol, BDNF, high-sensitivity C-reactive protein levels, miR-124 and miR-132 levels, distribution of immune-related lymphocyte subsets, and traditional Chinese medicine syndrome scores before and after 6 weeks of treatment. RESULTS: No significant difference was observed in any index between the two groups before treatment ( > 0.05). After treatment, the total efficacy rates were 93.33% and 90.00% in the experimental and control groups, respectively. Experimental group had significantly lower scores for the main and secondary syndromes compared to the control group ( < 0.05). No significant difference was observed in the metabolic equivalents between the two groups before and after treatment ( > 0.05). The levels of low-density lipoprotein cholesterol, high-sensitivity C-reactive protein, and miR-132 were significantly lower, whereas those of miR-124, BDNF, CD3+T lymphocytes, CD3+CD4+T helper lymphocytes, and CD3+CD4+/CD3+CD8+ cells were significantly higher in the experimental group compared to the control group ( < 0.05). The incidence of adverse reactions during experimental group was significantly lower than that in control group ( < 0.05). CONCLUSION: Shugan Jieyu capsules have good efficacy in patients with mild-to-moderate depression after PCI, and its mechanism may contribute to the regulation of miR-124, miR-132, BDNF levels, and lymphoid immune cells.