To investigate the generation mechanism of friction-induced squeal, a pin-on-disc test rig is firstly designed by utilizing an automotive brake disc, a friction pad and a round pin of Al alloy. Then the friction-induced squeal experiments are performed by adjusting the pin length. The finite element model is built up based on the constrained modal experiments of pin and disc. Finally, the influences of pin length, coefficient of friction, load, disc speed and material property on friction-induced squeal are investigated by using the complex eigenvalue analysis method. The results show that when the bending mode frequencies of pin and disc are closed to each other, the modes will be coupled, and the system will be unstable to produce squeal. Friction-induced squeal can be reduced or even eliminated by optimizing the structure, reducing the friction coefficient and adjusting the material property.