Kenya's major cities, particularly Nairobi and Mombasa, are experiencing rising average temperatures and frequent heat waves. While physical health impacts such as dehydration and cardiovascular strain are documented, the psychological toll remains underexplored. This paper examines the correlation between extreme heat events and mental health outcomes such as irritability, aggression, anxiety, and sleep disorders in urban populations. Data from hospital admissions, community surveys, and climate records highlight a rise in stress-related complaints during heatwave periods. The paper also explores socioeconomic disparities, showing that informal settlements are disproportionately affected due to poor housing conditions. The study calls for heat-mental health adaptation policies, including cooling shelters, climate-resilient housing, and mental health services integration into climate action plans.