Hollow fibers are commonly introduced into flexible thermoelectric materials for certain engineering applications. However, significant stress concentration may be caused in the vicinity of the interface between the fibers and thermoelectric matrix threatening the reliability of the composite structure. In this paper, we study the plane deformation problem of a rigid hollow fiber embedded in a thermoelectric material. By utilizing the complex variable method, the closed‐form solutions for electric, thermal and elastic fields in both of the fiber and the matrix are obtained. The effects of the thermal resistance and geometric parameters of the hollow fiber on the temperature and stress distributions are numerically examined. The results show that the temperature difference (amplitude of variation in temperature in the matrix side around the interface) and the stress field around the interface are proportion to the inner radius of the hollow fiber and the thermal resistance, respectively. Meanwhile, we find that the temperature and the stress distributions are more sensitive to the geometric parameters than to the thermal resistance. The results in this paper may serve as guidelines for design of fibers‐filled thermoelectric structures.