The accurate spatial 3D models and corresponding coordinates of every key point are needed to determine the sizes, shapes, and locations of installation for all curtain wall elements in the process of production and construction. To solve the transition problems between architectural design and construction design of curtain wall system, four kinds of single-constrained computer-aided 3D modeling algorithm for spatial point-line models were discussed in detail. Then, a multi-constrained iterative 3D modeling process was proposed by considering coupling relationships amongst the various constraints. A 3D modeling system named T3-CW-CAD was developed and applied to the Shenzhen Airport Terminal 3. The application results showed that the presented-algorithm can meet the overall demand for automatically generating multi-layer 3D models according to spatial point-line model, along with sizes and other restraints amongst curtain wall elements, therefore playing a key role in guiding the production and construction of curtain wall system.