Network analysis is a very important domain in GIS spatial analysis.This article mainly introduced two methods of performing Network Analyst in the ArcGIS Server 9.2 platform.In the first and the second parts of this article,the basic principles of Network Analyst in ArcGIS were introduced to the readers;and then two methods of the optimal path at ArcGIS Sever platform were given;finally,a comparison was given to illustrate differences between the two methods.