How colors are applied to provoke the aesthatic appearance of urban areas, could be regarded as one of the most significant questions. Then, it should be mentioned that colors placy a very crucial role in citizens behavioural patterns. As very impressive social elements, colors not only bring massages and convey meaning to their urban audiances, but enhance the visual attraction as well. This, however, has been always underestimated or even neglected in the case of Tehran as a very large city, where the colors are shaded by the lifeless gray left as the result of excessive air pollution, population boom and the huge number of motor vehicles.Hence, if very well identified, systematically organized and scientifically opted, colors would be able to pacify the inbaitates visual sense and help them concentrate even in chaos. Thus, it is necessary to point out that, every graphic designer, dealing with colors, merely takes the outer layers or clusters of the urban equipments, furniture, buildings and streets. Consequently, urban designers, architects and inclustrial designers are in charge of how to examine forms, masses and whatever belonging to urban spaces. The current study is an effort to firstly define the graphic design as a whole and then to provide the concepts of urban graphic and the relevant aspects. Next, color and their associated topics are dealth with. The last chapter presents a study conducted within the district no.5 to demonstrate how colors are being applied in Tehran and how they positively or negatively influence the city. The methodology is based in the field as well as librarical - documentational study. There are also photographical samples to enable the analysis and examine the currently applied colors.