This article presents student-teachers' perceptions of spatial 3D-descriptive geometry education in Mozambique. To interpret a 3D object through 2D projections and vice-versa requires spatial abilities that are deemed crucial for learning in any spatially dependent discipline such as 3D-descriptive geometry, engineering and technical-vocational disciplines. Such spatial abilities can be developed through training. In order to establish student-teachers' views on the main characteristics of spatial 3D-descriptive geometry education, an exploratory study was conducted employing a mixed-methods approach to elicit data from 120 participants at a higher education institution, through semi-structured focus group discussion. Data analysis was conducted using the technique of categorising themes from data, and using these themes developing a 40-item questionnaire. Exploratory factor analysis, multivariate regression and path analysis of the questionnaire responses were used to propose the study's model. The emerging theory shows a model for developing 3D geometry as consisting of four distinct factors: spatial visualisation and reasoning; evaluation and learning support; professional learning of geometry; and practice. The evidence shows that spatial visualisation and reasoning is seen as a main predictor of learning 3D-descriptive geometry. The data also show that further research is needed into 3D-descriptive geometry instructional material for its content validity. It would also be interesting if studies could be undertaken on students' perceptions of 3D-descriptive geometry education using more extended theoretical frameworks.