This thesis discusses the supportive role of color, form, and size in the recreational spaces in public complexes. The basic concepts, and the relationship of color, form, and size is presented. Human responses and semiotics of color, form, and size is studied with the perception, symbolic interpretation, and psychological responses. Application of color, form and size in the interior spaces are discussed and the roles of those features are analyzed by defining the space. The definition of the recreation is presented with its significance in human life and changes in its character. Public space is defined and the emergence of public complexes is introduced. The role of recreation on public complexes is discussed with its commercial, social, and psychological features. A field research is conducted to test whether there is a difference in the preference of color form and size for different activities and for different sexes in recreational spaces in public complexes, among 100 subjects in the Bilkent University dormitories.