The United Nations Sustainable Development Plan 2030, which is based on a "global call to action to end poverty, protect the planet, and improve the lives and prospects of everyone, everywhere by 2030," is one of the most ambitious and impactful global agreements in recent times. Specifically, Goal 13 of the Sustainable Development Goals (SDGs) focuses on climate action to protect the environment from ecological threats, which has later been translated into the green orientation across various sectors. In this context, Egypt launched the National Strategy for Climate Change 2050 during the COP26 summit in Glasgow, Scotland. The present study aims to examine the mediating role of green knowledge sharing in the relationship between Green Human Resource Management (GHRM) practices and both green promotive voice behavior and green prohibitive voice behavior within Egyptian banks listed on the stock exchange. The study collected primary data using a survey questionnaire, with a sample of 326 employees from 12 listed banks. Using Structural Equation Modeling-Partial Least Squares (SEM-PLS), the findings revealed that GHRM practices have a significant positive impact on both green promotive voice behavior and green knowledge sharing, while their effect on green prohibitive voice behavior was not statistically significant. Additionally, green knowledge sharing was found to have a significant positive effect on both green promotive and green prohibitive voice behaviors. Moreover, green knowledge sharing partially mediates the relationship between GHRM practices and green promotive voice behavior, while it fully mediates the relationship between GHRM practices and green prohibitive voice behavior. Finally, the study discusses the theoretical implications, practical applications, limitations, and future research directions.