Complexity has been known as a crucial psychological factor influencing the evaluation of the building facades preferences. However, little is known about the role of physical attributes of preferred building facades on perceived visual complexity. The objective of this study is to assess perceived visual complexity of urban building facades in terms of physical attribute in different levels. Discrete choice experiments were used to study the perceived visual complexity of preferred building facades. A sample of 213 students from Golestan University evaluated preference and perceived visual complexity of 36 pairs of images based on ten physical attributes of building facades in different levels (material (brick, stone), the contrast of materials (absent, present), color (absent, present), ornament (high, low), curve (straight, curved), vegetation (plants, no plants), windows orientations (vertical, horizontal), fenestration (large, small), articulation (side recesses, flat) and architectural style (modern, classic, traditional). The results revealed that all physical attributes of preferred building facades were found significant on perceived visual complexity expect for three attributes: architectural style, color and window to wall size. Thus, participant preferred a high-ornament facade with curved lines, vegetation, classical style, articulation, contrast between materials, as well as vertical windows. The articulation and ornament attributes were the most significant on perceived visual complexity. The results of this study can help city planners, architects, and designers to design facades with more general preferences and reduce the visual pollution of the cities.