Abstract: Military geology is an effective method for realizing the civil-military integration of military action, national defense construction and geological information.The keys of military geology study are to extract geological and geophysical elements related with military actions by studying the relationship among regional geology, engineering geology, hydrogeology, hazardous geology and geophysics and modern land area military action,to convert them into military geological elements and to integrate these elements with military targets, military topography and military actions, and then to form military maps that can be used by military personnel. According to the types of geologic information, the process of extracting and translating civil geological elements into military geologic elements can be divided into 5 broad categories, several classes and subclasses of military geologic elements index. Based on the process of extraction and using objects, the military geologic results are divided into two types:military geology conversion and application. Results of military geology conversion are the results of military geological elements, which are usedby military geology conversion personnel, serving as the intermediate results from geologic results to military geologic results. The application results are divided into two kinds:the military geological landform results for front-line combat personnel and the military geological thematic maps for front-line commanders. This paper refers to the conversion and expression from civil geology to military geology, which provides an idea for converting civil geological terms into military ones.