There are many factors of effect on the front wheel shimmy of motorbus,especially the front wheel alignment parameters have important effect on front wheel shimmy. Mathematical model of front wheel shimmy for motorbus, including main effect of front wheel alignment parameters, has been established. The digital calculation has been made to estimate the effect of front wheel alignment pa- rameters on shimmy. The correctness of research result has been verified from road test and motorbus repairing. The result in this paper can be used to guide fixing the breakdown related front wheel shim- my for motor vehicle with dependent suspension.