Abstract: In this paper, a simplified mechanical model for the crustal stress field around the Eerduosi block is provided. The Eurasian plate is simplified as an infinite, thin Hooke plate. The relatively stable and integrate Eerduosi block is modeled as a rigid elliptic inclusion embeded in the plate. Due to collision with the Indian Ocean plate and underthrust of the Pacific Ocean plate, the Eurasian plate is compressed in the direction of the westward underthruet of the Pacific Ocean plate. Using Muskhelish-vili's solusion for this problem, the crustal stress field around the Eerduosi block is analysed and calculated, and a possible explanation is provided for the character of the crustal stress field around the block. The crustal stress field of North China may be formed by the same source of force as the crustal stress field around the Eerduosi block, and a small regional stress field that exists around the block possibly reflects the important inhomogeneity of the medium.