Background: Climate change represents a significant global health issue that has rapidly ascended to the forefront of the global health agenda. Its impact can be profound, affecting individuals not only on a physical level but also psychologically and socially. Specifically, women are a population that may be particularly susceptible to the ramifications of climate change, and their quality of life may be threatened. It is worth noting that nurses are the frontline of any health system; therefore, it is essential to have a knowledgeable and skilled workforce to ensure the health of the community, particularly during crises such as climate change. Aim of the study: to assess knowledge and practices of maternity nurses related to the potential impacts of climate change on women's health. Design: A cross-sectional descriptive research design was implemented. Subjects: A convenient sample of 255 maternity nurses were enrolled from four maternity hospitals at Alexandria Governorate, Egypt. Tools: Data was collected using three tools namely, maternity nurses' basic data structured questionnaire, maternity nurses' knowledge related to the potential impacts of climate change on women's health structured questionnaire, and maternity nurses' practices related to the potential impacts of climate change on women's health structured questionnaire.  Results: the mean score of the overall knowledge is 36.40±7.84 with a total percent score of 62.77% indicating fair knowledge, while the overall practices were unsatisfactory in the majority (93.3%) of nurses with a mean score of 8.76±2.65. Conclusion:   The current study concluded that the overall score of maternity nurses' knowledge was fair while the overall mean score of their practices was unsatisfactory. Therefore, there is a gap between knowledge and practice.  Recommendations: It is suggested that the responsible authorities should conduct educational programs and training workshops to raise maternity nurses' awareness of climate change and its impacts on women's health as well as incorporating climate change in nursing curricula in all levels of study.