The AppellHamel constraint was studied. We prove that the AppellHamel constraint is stationary for Hamilton Action of nonholonomic systems, and has the same solution as the three mechanical modelsChetaev model, RosenEdelstein model and Vacco model. Finaly, using the theory that nonholonomic systems can be looked as holonomic systems under some conditions, we prove that the AppellHamel constraint has Lagrange equations of the second kind.