As a green cutting technology, Minimum Quantity Lubrication (MQL) machining process is used gradually widely in manufacturing industry. Compared with the external MQL system, the built-in MQL system has the characteristics of good permeability, little influences of chip, high efficiency and so on. In order to analyze the influence law of the injection characteristic of the built-in MQL system on the machining process, the built-in MQL system was developed on turning, and the orthogonal experiment with four factors and three levels was designed. The cutting force and surface roughness were determined as the evaluation indexes, and the cutting fluid flow rate, the air flow rate, the biodegradation lubricating oil and the cutting speed were selected as the variables in orthogonal experiment. The cutting fluids were sprayed along the flank to the tool tip in the high speed turning GCr15 bearing steel. Then the influence law of injection parameters on the machining process was analyzed. The optimized parameters are obtained, which have signifiant referance for engineering application in machinery machining.