The work aims to study effects of Na2SiO3 concentration on microstructure of micro-arc oxide (MAO) coatings on Ti3Al-based alloys and improve friction and wear properties of MAO coatings. Micro-arc oxidation coating was formed on Ti3Al-based alloy surface in Na2SiO3 electrolyte of 6 g/L, 8 g/L and 10 g/L concentration with constant current MAO power supply. The surface and cross-section morphology, element composition, thickness, phase structure and surface hardness of MAO coatings were investigated by SEM, EDS, Image J, XRD and micro hardness tester. Friction and wear properties of different micro-arc oxidation ceramic coatings were studied by CFT-I wear tester. With the increase of Na2SiO3 concentration, working voltages and striking voltages of MAO were reduced. The surface of the MAO coatings was porous, and there was an annular protrusion caused by the accumulation of the melt. With the increase of the concentration of Na2SiO3, the diameter of the micro pores on the surface of the MAO coatings was reduced, and the MAO coatings were gradually thickened. MAO coatings were mainly composed of Al2O3, SiO2, TiO2, Nb2O5 and Al2SiO5. The friction coefficient and wear rate of the coatings were decreased by MAO treatment. When the concentration of electrolyte was 10 g/L, the average friction coefficient was 0.49 and the wear rate was only 2.1×10-7 mm3/(N?mm). The wear mechanisms were dominated by micro cutting wear, along with some adhesive wear. With the increase of Na2SiO3 concentration, the formation rate of MAO coating is increased and the reaction time is shortened. The wear resistance of Ti3Al-based alloy can be significantly improved by micro-arc oxidation treatment.