This work proposes a homogenization method for micropolar elastic bodies aiming at their multiscale optimization. Micropolar continuum theory is a generalized continuum theory and enables us to accurately analyze certain materials that have singular properties due to their microstructures. The main difference between micropolar continuum theory and classical continuum theory is that in the former, each material point has independent rotational degrees of freedom in addition to usual translational degrees of freedom. In order to generate materials with new or improved properties not found among existing materials based on multiscale optimization for micropolar elastic bodies, we need to formulate a homogenization method in which heterogeneous materials can be replaced with mathematically equivalent homogeneous materials. In this work, the governing equations for both the microscale and macroscale are developed through an asymptotic expansion. Numerical examples are shown to confirm the validity of the proposed homogenization method and the potential for multiscale optimization.