The sewing machine needle bar will tilt under complex forces in the actual movement process.In order to study the influence of the needle bar inclined state on air flotation properties of bearing and the influence of gas on the needle bar,the physical model of needle bar tilting was established,the gas film height surface of upper and lower bushings was simulated.The pressure distribution of gas film was calculated based on MatLab and by using the finite difference method,and the static characteristics of gas bearing were analyzed.The results show that,the larger the tilt angle of needle bar,the bigger the flotation capacity,the greater the countertorque produced by gas on the needle bar.The difference of gas membrane between upper and lower bushings is obvious,the upper shaft has gas big stiffness,and a dynamic pressure effect will generate if the needle bar is in high speed movement.