Modeling with UML of pre-battle decision support system and the application of the model are mainly discussed in this paper. Common model of pre-battle decision support system and the description with UML of it are introduced firstly, and then the aided decision-making system of units' deployment are analyzed and designed with UML, the arithmetic models needed by the system are also given. In the end, some part of code is generated by Rational Rose, the CASE tool, from the UML model, and the software system...