The purpose of this study was to evaluate the effect of environmental performance mediator role on the effect of green supply chain management on export performance of exporting companies in Guilan province. The purpose of the study is applied and descriptive - survey type. The statistical population of the study consisted of the selected exporting companies in Guilan province in the year 1977. The data collection tool was a standard questionnaire whose validity was confirmed by content validity and its reliability by Cronbach's alpha test. Structural equation modeling based on partial least squares approach was used for data analysis by Smart PLS3 statistical software. The findings showed that green supply chain management has a positive and significant effect on environmental performance and export performance of exporting companies in Guilan province. The impact of environmental performance on export performance of exporting companies was also confirmed. The mediating role of environmental performance on the impact of green supply chain management on export performance of exporting companies of Guilan province was also proved. Overall, it can be said that by improving environmental performance, the impact of green supply chain management on the export performance of exporting companies in Guilan province will improve. تفاصيل المقالة