Designing library study environment is important to the mood, motivation and performance of individual because interior design plays an important role on human mood and social behaviours. Lighting, as a control architectural tool, gives important influences on users’ perception behaviour and visual comfort in libraries. A public library in Shah Alam was chosen as the main subject. The result found that the library users prefer the seat near daylighted area, but the time spend in the library is not really affected by daylighting. Besides for visual comfort, daylighting is not the only contributor to overall comfort and user’s satisfaction.