计算机网络在为人类造福的同时，也为病毒的传播提供了便利。在网络环境下，病毒传播的范围扩大了，速度大大加快，网络已成为近年来病毒传播的主要途径。针对病毒在网络上传播的新特点，分析了网络环境下病毒传播的主要模式，包括E-mail传播、主动扫描传播、通过服务器传播等，介绍了业界的一些对策，并给出了一般用户有针对性的应对措施。

The computer network is not only of benefit to the people, but also helpful for the spreading of viruses. The net-viruses spread more widely and rapidly than the traditional viruses, and network has become the major way of the virus spreading. This article analyzes the mode of the net-virus spreading, including E-mail spreading, positive scanning spreading and through-server spreading. Then some defense strategies in the antivirus field are introduced, and some countermeasures of the net computer users are discussed.