In order to investigate the influence of misalignment on the meshing characteristics of double circular arc gear pairs,a gear loading analysis model based on finite element method was established.The contact performance of single tooth convex and concave tooth profiles during the meshing process was studied,and the influence of misalignment on contact performance and transmission error was compared and analyzed.The research results show that during the meshing cycle,the concave tooth profile of the double circular arc gear first contacts and bears a large normal contact force,but the contact stress at the meshing end of the convex tooth profile is the highest,and the contact pressure difference between the convex and concave tooth surfaces is proportional to the torque; misalignment has a significant impact on the contact performance of the tooth surface,the center distance errors easily causes stress concentration at the gear step,and misalignments on the axis plane can cause tooth surface contact deflection， and it has the greatest impact on installation errors.