Background: Climate change includes both global warming caused by humans and its impacts on Earth's weather patterns.  The study aimed to: assess mother's awareness about the effect of climate changes on health of their children under 5years . Research design: descriptive exploratory design was utilized to achieve the aim of this study. Setting: The study was conducted at Elamiria Medical  Center in Elzaton Zone. Sample: A Purposive sample of 264 enrolled at the above mentioned setting was involved in this study. Tools: One tool was used for data collection structural interviewing questionnaire: It was included three parts as following: Part (I):  mothers Socio demographic data. Part (II): mothers Knowledge about climate changes effects on health of their children. Part (III): mothers reported practices about climate changes effects on health of their children. Results:  the present study showed that 61.4% of the studied As regard to total level of knowledge of the studied  mothers had unsatisfactory level of knowledge about the effects of climate change on the health of their children. While, 38.6% of them had satisfactory level of knowledge. As regard to total level of practices of the studied mothers related to the effects of climate change on the health of their children, the current study result illustrated that 52.3% of the studied mothers demonstrated healthy practices related to the effects of climate change on the health of their children. While, 47.7 % of them demonstrated unhealthy practices. Conclusion   there was a significant statistical relation between total level of knowledge and total level of practice among the studied mothers. Recommendation: Awareness programs should be conducted regularly for improving mothers' knowledge which could positively affect their perception and daily life practices and their children health regarding climate change. Apply further research about climate change in other setting for generalization. Mothers need to have adequate knowledge regarding nutrition for under fives and how much it is important for children's growth and development.