It was previously established that mental health workers in Rwanda experience secondary traumatic stress (STS) when working with trauma survivors. The effects of STS can be serious and permanent in mental health workers when working with traumatized clients. This study aimed to develop an intervention model to manage STS in mental health workers in Rwanda. It was carried out into five cycles using action research approach.A total of 180 participants were selected using convenience sampling to collect quantitative data. 30 unstructured interviews were also conducted to collect qualitative data. Experts from mental health services were also involved in development of the model based on the qualitative and quantitative data as well as literature review.A diagrammatical model to manage STS was developed by mental health professionals. The key elements to include in the model were based on preventive, evaluative and curative strategies to manage STS in mental health workers in Rwanda. During the evaluation of the implementation, it emerged that participant noticed a change in coping strategies when facing the stressful incident in the practice.