The quality of the light around us has a profound impact on our emotional well-being that should not be underestimated. This research will focus on the lighting inside hospitals' rooms and health care amenities, starting with a brief research about lighting designs in hospitals in general and its design principles. Through research, general studies and case studies, this research then will identify the mechanisms of the lighting design by focusing on how light impacts human health and performance in the interior spaces, and review the literature linking light with health outcomes in healthcare settings. In addition, the research will cover the appropriate types and best distributions of light fixtures inside all the spaces of a hospital including entrances, corridors, waiting rooms, examination rooms, imaging rooms and patient rooms. The importance of this research is visible in the benefits and outcomes of the lighting when it's well applied in hospitals. Choosing the right light in the right place would help to enhance the healing of a patient and make his staying -at a hospital- better, improve doctors and staff functionality, and create a healthier and better environment.