Based on linear micropolar thermoelasticity theory, a two-dimensional boundary element method (BEM) formulation is derived and the corresponding computer programs are developed to solve the problems of micropolar solid. The program is verified by computing the thermal stress in a hollow cylinder. In addition, the new BEM formulation is applied to solve, for the first time, the thermal stress of a square region with a circular hole. The effects of coupling number and characteristic length on the micropolar effects are derived, and the important new findings are summarized.