An experimental system for the rockbreaking mechanism of disc cutters of TBMs is developed, so as to observe the rock fragmentation effect and rock microcracking effect of disc cutters. Comparison and contrast is made between two experimental system options, i.e., vertical experimental system and horizontal experimental system, and in the end the former is adopted. The component, main structure, installation and debug of the experimental system adopted are described in detail. The experimental system is capable of making the following tests: 1) Tests on the stressing formula of disc cutters; 2) Tests on the optimum disc cutter spacing under different rock conditions; 3) Tests on the relationship among the stressing, penetration rate and spacing of disc cutters. Some national 973 research items are studied by means of the experimental system developed, which shows that the experimental system developed is applicable, advanced and rational. The experimental system developed provides a public platform for researches on the rockbreaking mechanism of disc cutters. 