This study was to explore mechanical majors' spatial ability in engineering graphics at normal universities. Relevant documents on spatial ability were first discussed so as to serve as the theory basis of the study. Expert meeting discussion was then used to construct the scale of spatial ability, and from a series tests on spatial ability in engineering graphics, the data collected were analyzed in statistical methods to conclude the standard module of the spatial ability scale, as well as the difference between the spatial ability of the students at National Taiwan Normal University and that of the students at National Changhua University of Education.
The conclusion were as follows:
1. The spatial ability scale has good reliability and validity.
2. The Stanine model can be used to represent the standard module of students' spatial ability.
3. The spatial ability of the mechanical majors at National Taiwan Normal University was better than that of the students at Notional Changhua University of Education.