We have made crystallographic analysis for microstructures formed by charge ordering transitions in Pr0.55Ca0.45MnO3 and Nd0.5Sr0.5MnO3. From the results, it was found that all interfaces between crystallographic domains of Pr0.55Ca0.45MnO3 are {101}(CO) (CO represents a charge ordered phase) twinning planes and that most of interfaces between crystallographic domains of Nd0.5Sr0.5MnO3 are {112}(CO) twinning planes. These twinning planes correspond to {110} planes in simple cubic perovskite structure.