Purpose: This study developed an integrated health management program for metabolic syndrome in psychiatric patients and examined its effects on self-efficacy, healthy lifestyle, physiological indicators, knowledge of metabolic syndrome, attitudes toward healthy behavior, and social support. Methods: A non-equivalent control group pretest posttest design was used. The participants were 65 psychiatric patients with metabolic syndrome in psychiatric rehabilitation centers, with 33 in the experimental group and 32 in the control group. The experimental group participants engaged in daily mobile application and walking exercises three times a week for more than 40 minutes over 8 weeks, while those in the control group were provided education booklets. The outcomes were measured using self-report questionnaires, anthropometrics, and blood analyses. Intervention effects were analyzed using the independent t-test, Mann—Whitney U test, ANCOVA, and Ranked ANCOVA. Results: The experimental group showed a significant increase in self-efficacy (F = 8.85, p = .004, ηp2 = .13) and knowledge of metabolic syndrome (t = 2.60, p = .012, d = 0.60) compared to the control group. Additionally, the experimental group demonstrated a significant decrease in waist circumference (Z = - 2.34, p = .009, d = 0.58) and body mass index (Z = - 1.91, p = .028, d = 0.47) compared to the control group. Conclusion The integrated health management program for psychiatric patients with metabolic syndrome is effective in improving self-efficacy and knowledge of metabolic syndrome and decreasing physiological indicators such as waist circumference and body mass index.