With the advance of "general enrollment and diversion training" pattern in local institutions, the problems of specialty differentiation in the division of architectural specialty are increasingly outstanding. This paper finds that major selection is influenced by six factors and three levels by analyzing students’ process of thinking constructing. In the usual diversion pattern, the major selection presents two consistency deviations of architectural tendency even though the prospect and subject strength are similar between two majors. Cognitive image causes the first deviation in major selection, and mere exposure effect reinforces the first deviation while group psychology leads to the second deviation. Therefore, it is an important guarantee for the overall planning of specialty construction to formulate targeted coping strategies and optimize specialty diversion mechanism.