Aiming at the problem in geotechnical testing, which is the critical part when teaching the course of Soil Mechanics, a portable miniature soil triaxial apparatus was developed in order to optimize teaching mode, strengthen classroom interaction and combine theory and experiment teaching process. Guided by the purpose of learning the theoretical knowledge and improving practical ability, students can better master the testing method and process of the triaxial test, understand the effective stress principle more intuitively and vividly, and enhance the knowledge related in the course of soil mechanics. The practice shows that, due to the small size, light weight and portability of the triaxial apparatus, as well as it can simulate the consolidation, shearing and drainage control functions of the actual triaxial apparatus, the demonstration using it in the theoretical course is helpful for students to master the key operation steps of different types of triaxial tests. Intuitively understanding the important principle that effective stress determines the strength and deformation characteristics of soil can stimulate the learning enthusiasm of students, improve their comprehensive practical ability, and effectively improve the teaching effect of related content in soil mechanics courses.