Abstract: Research progress and present status of preparation and application of chemical manganese dioxide (CMD) were reviewed．Several common preparation methods,such as manganese carbonate thermal decomposition method，manganese nitrate thermal decomposition method，solution oxidation-reduction method,and nano-MnO₂ preparing method,were introduced，and advantages and disadvantages of these methods were analyzed．At present，the main industrial production methods of CMD are manganese carbonate thermal decomposition method，manganese nitrate thermal decomposition method,and manganese sulfate-potassium permanganate oxidation-reduction method.Preparation and application of nano-MnO₂ are important developing directions of CMD． 

Key words: chemical manganese dioxide, preparation methods, research progress