Abstract: With the promotion of conceive–design–implement–operate (CDIO) teaching concept in domestic universities, experimental teaching is more and more important for students' learning. However, the traditional conventional tri-axial mechanics experimental device has high cost and the experimental process is dangerous. In order to overcome these limitations and make the device be widely used to the students' practice, a tri-axial teaching experimental device was designed. The device eliminates the huge frame structure in the conventional device, and has the characteristics of large rigidity, small volume, low cost, and safe operation. It is conducive to stimulating students' scientific research interest in experimental teaching and cultivating students' hands-on practical ability.