Abstract: For the same holonomic nonconservative system,the expression of the Lagrange equations under different generalized forces appear different.For different expressions of the equations,the Noether symmetry,the Lie symmetry and the form invariance can be changed.The result of this paper expresses that the gauge function in the Noether identity is changed,but the Noether conserved quantity is not changed.In this case,the Lie symmetry is not changed and the form invariance is changed. The condition under which the form invariance is changed is given.