The research aims to assess the role of Ecotourist in achieving sustainability in the Region of the Gulf of Aqaba by focusing on the following dimensions (Environmental knowledge، Environmental attitudes, Environmental behavior) and examining the impact of those dimensions in achieving sustainability. The importance of this research is enriching the scientific content related to Sustainability and the role of Ecotourist in achieving it by focusing on Environmental knowledge, Environmental attitudes and  Environmental behavior as there is a lack in studying the variables that affect the achievement of sustainability in the Ecotourism destinations. The study used the analytical descriptive method to determine the relationship between the study variables and the field study was conducted by distributing questionnaires to a sample of (366) tourists in the two reserves of Ras Muhammad and Abu Jallum in the Gulf of Aqaba Region. The results indicated that Environmental Education contributes to increase awareness, knowledge and attitudes needed to build responsible behavior towards the environment which leads to the sustainable use of natural resources. The study recommends the necessity of increasing the number of Environmental researchers working in the Natural reserves of the Gulf of Aqaba in order to explain and educate the large numbers of tourists who visit those reserves.