The work aims to optimize preparation technology of TiN coatings by studying effect of N2 flow rate on the microstructure and properties of TiN coatings deposited by plasma enhanced magnetron sputtering. TiN coatings were prepared by plasma enhanced magnetron sputtering at different N2 flow rates. Surface morphology of the coatings was observed with 3D profilometer and scanning electron microscope, phase composition with X-ray diffractometer, hardness with a microhardness tester, friction and wear propertieswith ball-on-disk friction and wear tester, and chemical composition of griding cracks with energy disperse spectroscope. When N2 flow rate was less than 61.5 mL/min, total gas pressure and target voltage were slightly affected as N2 flow rate increased; but when N2 flow rate was over 61.5 mL/min, the total gas pressure and target voltage increased dramatically as N2 flow rate increased. With the increase of N2 flow rate, intensity of TiN(111) and TiN(220) diffraction peaks increased gradually while that of TiN(200) kept constant firstly and then declined sharply. The TiN-coated samples of the best compactness and highest hardness were obtained at the N2 flow rate of about 61.5 mL/min. The TiN-coated samples of wear rate as low as 7.4×10-16 m3/(N?m) were obtained at the N2 flow rate of 50 mL/min to 61.5 mL/min. However, wear rate of the TiN-coated samples increased significantly at the N2 flow rate of over 63 mL/min. Preferred orientation, hardness and friction and wear properties of the TiN coatings deposited by plasma enhanced magnetron sputtering are obviously affected by N2 flow rate, and the best hardness and abrasion resistance can be obtained at the N2 flow rate of about 61.5 mL/min.