We study inelastic dark matter-nucleus scattering in stopped pion experiments by nuclear shell model. We find that the inelastic scattering is dominated by Gamow-Teller (GT) transition. We use nuclear shell model code, BIGSTICK, to calculate GT transitions and the deexcitation photons for the nuclei such as Na-23, Ar-40, and I-127. Given the experiment setup at stopped pion experiment (e.g., CCM and COHERENT), we can utilize the photon spectrum and determine the event rate for inelastic scattering. We find new regions of light DM parameter space that can be probed.