Background and aim: Due to the prevalence and adverse consequences of stress at work, implementing practical programs are necessary for a systemic approach to identifying various stress risk factors and preventing them. This study was conducted to survey and analysis the stress prevention at work, using the participatory ergonomics process to improve the competence (both technical and social skills) of employees in one of the Iranian Gas Refineries in 2017. Material and Methods: This research is a descriptive-analytic study of cross-sectional type. Firstly, after expert evaluation using the stress prevention at work checklist and ELMERI index, 59 people (from different levels of the organization) were selected by randomized sampling and census method, and were assigned to 10 different workgroups. During the two phases, individuals completed and presented checklists and checkpoints in technical meetings. During these technical meetings, the workgroups were involved in the participatory ergonomics process based on the action learning approach, and provided practical and cost-effective solutions to work problems. Then, to receive feedback from participants and evaluate the study, a questionnaire was used in two different the phases and an evaluation workshop were held. The results were analyzed using SPSS25 software. Results: The results of expert-based assessment showed a score of 4.16, which indicates the need to investigate and intervention. The statistical results of the checklists used by the workgroups also showed a significant difference before and after the using of the stress prevention checkpoints at work. Moreover, the results of the questionnaires and evaluation workshop indicated the effectiveness of the participatory ergonomics process, action learning, improved communication, and good teamwork interaction were identified in order to better identify problems and cost-effective solutions. Conclusion: According to the theoretical and empirical evidences of this study, it can be concluded that participants, getting into the joint learning process by the participatory ergonomics process, action learning approach and awakened need to change. The output was a systemic pre-intervention work to promoting of the competency (both Technical and social skills), and also organizational skills of the participants and internal facilitator. © 2020 Iran University of Medical Sciences. All rights reserved.