Abstract: Objective To expand the application of toluidine blue staining. Methods Skin, lung,trachea, cerebrum and spinal cord tissues were collected and fixed by 4% formalin. After routine slicing,the slices were stained by toluidine blue. Lastly the feature of all kinds of tissues under microscope was observed. Results Besides nissl body was clearly showed，the langerhan's cell, melanocytes and merkel cell in skin can also be differentiated. The type I alveolarenhanced by toluidine blue staining.The layers of cerebral cortex were displayed much more clearly than HE stai cell，type II alveolar cell and macrophage in lung and the ciliated cell and goblet cell in trachea were markedly ning. Conclusion Toluidine blue staining may be explored in skin, lung, trachea, cerebrum and spinal cord tissues.

Key words: Toluidine blue staining, Histology, Rat