To achieve high safety levels, mere compliance with safety regulations is not sufficient; employees must be proactive and demonstrate safety citizenship behaviors. Trust is considered as a mechanism for facilitating the effects of a leader on employee citizenship behaviors. Increasingly research has focused on the role of trust in a safety context; however, the role of coworker trust has been overlooked.The mediating role of coworker trust in the relationship between the leader-member exchange and safety citizenship behavior is the focus of this field study.Front-line employees from an air traffic control center and an airline maintenance department completed surveys measuring leader-member exchange, co-worker trust, and safety citizenship behavior.Structural Equation Modeling revealed affective and cognitive trust in coworkers is influenced by leader-member exchange. A trust-based mediation model where cognitive trust and affective trust mediate the relationship between the leader-member exchange and safety citizenship behavior emerged.Results of this study add to our understanding of the relationship between leader-member exchange and safety behavior. The effect of co-worker trust and the extent to which employees participate in workplace safety practice were identified as critical factors. The findings show that managers need to focus on developing cognitive and affective coworker trust to improve safety citizenship behaviors.