As green human resource management is known as a way of promotion of sustainable employee practices with the help of interface of every employee, there has always been a question in mind why in some societies green human resource management practices cannot be implemented effectively. The purpose of this paper is to find factors affecting green human resource management practices as barriers to help managers identify the root and be able to surmount the obstacles. As the result showed two groups of factors were defined; 1- Internal factors including personality and upbringing, knowledge of individuals, organizational culture, and 2- External factors including digital divide and education and training. Then the attention is drawn to the significance of these factors to see which one can have the most and the least effect. Therefore to rank the value of these factors the Friedman test was used. The result showed that among all these factors personality and upbringing have the highest effect and digital divide has the lowest effect on green human resource management practices. It is believed that by emphasizing and paying more attention to these factors the implementation of green human resource management can be improved more effectively and employees will be more willing to show green behavior towards the environment or the use of resources.