The researcher study the color concept in modern age, and clarify the theories of harmony and contrast of colors. Also he talked about the color philosophy, which include a study of the relation between color and shape, form, space…, and a study of the psychological' colors effects on number of interiors, Residential, Educational, Cultural, Commercial, Health care… Finally, the research end to give the most important considerations and steps that should be followed in the study to any color scheme of an interior space, in a way that achieve the functional aspect as first, and aesthetic aspect as second.