In the modelling approach of bar turning, the accurate prediction of the Chip Flow Direction represents a real challenge; it directly affects the axial and radial components of the cutting forces, and consequently the temperature distribution in the rake face. Chip flow direction is one aspect of chip control which is an important key factor in turning operations optimization. The aim of the present work is to propose an analytical approach of modelling to determine the chip flow direction in bar turning. Experimental tests and results complete the study and validate the proposed model.