The backward substitution method is a recently proposed semi-analytical meshless collocation method. The main idea of the back substitution method is to obtain the boundary approximation from the boundary data, and this approximation does not need to satisfy the governing equation. Then, the traditional linear combination of basis functions is used to construct a correcting approximation that satisfies the homogeneous boundary conditions, the numerical solution is given by a linear combination system of boundary approximation and modified approximation, which satisfies the governing equation. In this way, the backward substitution method can be easily used to solve general problems without fundamental solutions or particular solutions. This paper makes the first attempt to extend the backward substitution method to the simulation of inverse Cauchy problems in piezoelectric structures. For the inverse Cauchy problems, the absence of data on some boundaries often leads to extreme instability of numerical solutions. A simple method is applied in this paper. For the points on the boundary without boundary information, the governing equation is enforced. Numerical results demonstrate that it will greatly increase the stability of the solution process.