Introduction: This study measured the outcome of the Optimal Health Program (OHP) among frontline healthcare workers during the COVID-19 pandemic. The OHP is a wellness-based self-management intervention focused on well-being to gain optimal health. OHP is originally from Australia and has been translated, culturally adapted and branded as the Program Kesihatan Optimum Sanubari (SANUBARI). The program was conducted as a psychosocial intervention and the outcomes measured were self-efficacy, coping styles and well-being. Methods: Eligible participants were nurses who actively managed COVID-19 inpatients in Hospital Kuala Lumpur and committed to complete the intervention. Those who did not provide consent or had comorbidity, unstable medical or psychiatry illnesses were excluded. 43 nurses were recruited through convenience sampling method and completed outcome measures from General Self-Efficacy Scale, Brief COPE and WHO-5 Well-being Index, before and 1-month after the intervention. The OHP was conducted via group-based, using OHP Sanubari workbook with 5 weekly sessions by trained facilitators and lasted for 60 to 90 minutes per session. Results: Significant improvement was observed 1-month post intervention for self-efficacy (t(42)=5.64, p <0.001) and well-being(t(42)=2.14, p<0.05); different approach coping strategies(acceptance, use of informational support, positive reframing, active coping, and planning) and avoidant coping strategies(distraction, venting, denial, and substance use). Whilst, humor coping reduced significantly 1-month post-intervention (t(42)=3.66, p<0.05). Conclusion: This study reports the positive outcome of OHP on the mental health status of healthcare workers during the pandemic. This program can be considered as a tool towards optimal health throughout their career.