Gear transmission is widely used in equipment manufacturing and the defense industry. With the development of industrial modernization, high reliability, high carrying capacity and low noise requirements have been put forward for gear transmission. The arc tooth cylindrical gear is derived from the curved tooth bevel gear. And its tooth line is a space circular arc, which has the advantages of good contact ratio, no axial force, good meshing performance, low noise, strong carrying capacity, etc. In most cases, it can replace the straight tooth, helical tooth and herringbone gear transmission. As a new type of transmission, the research on the meshing principle and transmission characteristics of arc tooth cylindrical gear is not systematic enough. Therefore, this kind of gear transmission mode has not been widely used. This paper introduces the research status of arc tooth cylindrical gear transmission and analyzes the arc tooth cylindrical gears meshing principle and transmission characteristics. Firstly, the basic rack of arc-tooth cylindrical gear is constructed based on the reference profile of involute gear. The tooth surface equation of arc tooth cylindrical gear is derived according to the meshing principle of pinion and rack. Based on the tooth surface construction method to establish a three-dimensional solid model. The calculation formula of contact ratio was derived, and the influence of different arc radii on contact ratio was studied. Based on the theoretical analysis of the contact strength of spiral gear, the influence of different design parameters on the contact stress of spiral gear was studied. Based on the finite element method, the contact stress of spiral gear is analyzed and compared with the theoretical calculation value, which proves the accuracy of the theoretical calculation method.