Abstract: The different mechanical properties in mortar and in aggregates may lead to stress concentrations in concrete. However, as the distribution of aggregates is very complicated, a numerical analysis of concrete on micromechanical scales will involve a large computation and the difficulty of element meshing. Therefore, analytical solutions for the stress concentration factor caused by the existence of aggregates are derived in this paper based on a 2D model. Then, together with the superposition method, analytical solutions are used for the stress analysis in concrete of homogeneous media to approximate the real case, which makes the problem much easier. Analytical results are compared with those obtained by the FEM method for concretes with one aggregate and four aggregates, respectively, which verifies the accuracy of the method given in this paper.