This research focus on the squeals occurred in cutting from the views of tribology. A multi-degree-freedom model was established referring to cylindrical turning. The model was made up of two coupled subsystems — tool and workpiece which coupled through the friction between their contacted surface. The relationship between cutting squeal and friction was studied through experiments, and the coefficients of friction were estimated by experimental data. Then the tribological conditions related to squeal generating were discussed. In the end a method of reducing cutting squeal by lubrication was proposed.