Assembly errors can significantly affect the smoothness, vibration, and noise of Spiral bevel gearing. This work delves into the impact of installation errors on the meshing performance of Spiral bevel gear drives. By establishing a mathematical model for tooth contact analysis that includes installation errors and using numerical analysis software to solve the gear meshing equations, we have determined the effects of different installation errors on the tooth contact patterns of bevel gear drives. Additionally, a finite element analysis model of bevel gears was built to conduct dynamic contact analysis under the consideration of installation errors, examining variations in driven gear speeds and tooth contact stresses. The study reveals the patterns of influence that different installation errors have on tooth contact patterns, driven gear speeds, and the numerical values of tooth contact stresses. The results provide theoretical support and practical guidance for the design, manufacturing, and assembly of bevel gear drives.