The invention discloses a distributed PDM system data transmission monitoring method based on a Web. A system module employed in a monitoring process of the monitoring method comprise a distributed PDM system, a data transmission monitoring and PDM system interface module, a server monitoring module, a data transmission monitoring module, a Web page display module, a user management module and a Web monitoring server. According to the method, a server is detected in real time before data is transmitted, so the accuracy and availability of the environments of two PDM subsystems are ensured. Operation states of the server are identified in a graphic mode according to different colors. Data transmission queue information and comparison information are automatically obtained by the system, and problems occurring in the data transmission process are processed in real time. Real-time deadlock condition of a database of each PDM subsystem is monitored, and detailed deadlock information is recorded. According to the system, through adoption of a central management mode based on the Web page, a distributed PDM system manager can centrally manage the data transmission problems of the PDM subsystems of different regions; the repeated work is reduced; and the working efficiency is improved.