Traditional public art generally carries the value of elite culture and continues the cultural value orientation of classical art. In recent years, with the cartoon image entering the field of public art, the public aesthetic value representing the common people has also entered the value category of public art. With the development of industry and commerce, the mainstream traditional elite culture gradually complements the popular culture and vice versa. The collision of classical aesthetic values and popular aesthetic values enriches the social and cultural forms and meets the spiritual needs of different classes. Cartoon art came into being in the confrontation with traditional art after the Middle Ages, and has appeared in the form of popular culture since modern times. The intervention of cartoon image in public art makes its values turn to civilian society and expands the participation of public art. This paper analyzes the audience, psychological factors and forms of expression of public art and culture of cartoon image through the cases of cartoon image intervening in public art at home and abroad, and sorts out the expansion of contemporary public cultural values.