Various modifications of manganese dioxide have been discussed in terms of the chemical analysis by differential heating curve. The transformation temperatures of the modifications were observed as follows; ${alpha}-;and;{eta}-MnO_2$ are both $580^{circ}C∼650^{circ}C$, ${gamma}-MnO_2$is is $405^{circ}C~605^{circ}C$ and ${delta}-MnO_2$is $860^{circ}C~875^{circ}C$, respectively. Endothermic peaks appeared at the transformation temperatures mentioned above. The restoration temperatures of transformation is completed depending on the amounts of the given samples, but the temperatures of the top of endothermic peaks are nearly constant. The curves of ${alpha}-,{eta}-MnO_2$and ${delta}-MnO_2$ show small peaks while that of ${gamma}-MnO_2$ shows a sharp and broad peak.