Title: Safety competencies: A systematic literature review. Background: Safety competency is believed to be a pillar of an organization’s safety culture and one of the safety climate dimensions. Safety competencies can be a vital point to controlling and maintaining the sustainability of safety and health in a society and organization. The sustainability of the industries’ and society’s safety relationship can be driven by the controlled hierarchy in the society and the competencies of its members. Failure to identify social sustainability indicators such as a leading competency in safety will cause a failure in the safety development program. Hence, a systematic literature review of published studies is essential for easing the dissemination of useful research findings and gaining access to future trends in safety competencies research. The review aimed to identify studies about safety competency and identified the basic safety competencies for the workforce to maintain a sustainable safety climate. Methods: This review provided a five-step approach guided by The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement and published systematic review framework. The studies from the past 20 years were retrieved from electronic databases such as Scopus, Science Direct, and Web of Science. The review only involved article papers, research papers, and review papers which are written in English. The quality of the review was assessed using a standard PRISMA 2020 checklist. This review is registered on the International Platform of Registered Systematic Review and Meta-Analysis Protocols (INPLASY) with registration number INPLASY202230246 and DOI number 10.37766/inplasy2022.3.0146. Findings: The unbiased and wide review produces a new, feasible alternative to a social sustainability safety index. The number of studies on safety competencies study has expanded in recent years which shows the importance of the item to sustain the safety climate. This review suggests teamwork, communication skills, and a foundation of safety knowledge as the basic safety competencies for workers based on the competencies being most discussed. The review process suggests the possibility of future research regarding safety competencies after a catastrophic event such as the COVID-19 pandemic and sustainability of industrial safety regarding human-machine integration through 4.0 Industrial Revolution era.