Purpose This study aims to reveal whether green perceived organizational support has a mediating role in the relationship between managers’ green transformational leadership and the green self-efficacy beliefs of employees. Design/methodology/approach The textile industry is a sector with fast and cheap production and is the second most damaging sector to the environment due to excessive consumption and rapidly changing fashion trends. Hence, textile industry employees were selected as the research object. The data were collected by survey method from 274 people working in businesses operating in the textile sector in Türkiye. The collected data were analyzed in the SmartPLS 4 analysis program. Findings The analysis found that managers’ green transformational leadership increases employees’ green self-efficacy beliefs. Likewise, it was determined that managers’ green transformational leadership increases employees’ green perceived organizational support. The analysis also indicated that employees’ green perceived organizational support increases employees’ green self-efficacy beliefs. Finally, as a result of the analysis, it was concluded that green perceived organizational support is a complementary partial mediator variable in the relationship between managers’ green transformational leadership and employees’ green self-efficacy beliefs. Originality/value The available literature has overlooked the mediating role of green perceived organizational support in the relationship between managers’ green transformational leadership and the green self-efficacy beliefs of employees. This work makes new contributions to the literature and practice by revealing the significance of managers’ green transformational leadership and green perceived organizational support in increasing employees’ green self-efficacy beliefs.