The purpose of this project is to develop a graphical tool to analyze and optimize the image flow pattern in a hierarchical, large scale PACS local area network. The PACS network is characterized as heavy image traffic, long image flow path, heterogeneous computer nodes, multiple protocols, and physical media. A smooth operation of the PACS network depends on a centralized, timely report of image flow pattern, trouble spots, and an alarm mechanism for critical conditions. Crucial timing parameters such as queue delay from acquisition to display, processing time for archiving and reformatting, and retrieval speed, can be locally collected and reported to the network manager for statistical characterization. Moreover, network traffic information and system component failures anywhere in the image flow can be reported graphically. High urgency failure trigger an immediate alarm to the designed operator. Our network management software with user friendly graphical interface is easy to use even by non-computer personnel such as hospital administrators. It achieves total automation in trouble reporting and thus leads to improvement of the network layout and operation condition based on the analysis of image flow pattern.