The nonlocal residual symmetry related to 1 1 truncated Painlevé expansion of third-order Burgers 2 equation is performed. Then, the potential symmetries 3 of the equation are derived; on the basis of nonlo-4 cal symmetries, we linearize the nonlinear third-order 5 Burgers equation to a linear third-order PDE. Further-6 more, the exact solutions of the potential equation are 7 presented in terms of the symmetries. In particular, con-8 servation laws are constructed of the equations.