Downlink meteorological data is a very important data source for provincial meteorological service, which is the base of weather forecasting, climate prediction, and weather and climate research. The receiving process of downlink meteorological data is analyzed, and the construction idea of the Jiangxi downlink meteorological data monitor platform is presented. On the basis of log analysis, MVC framework, SQL Server database, HTML, and JavaScript technologies are used to design and develop the monitor platform. The realtime monitoring of the downlink meteorological data, such as download data and CMACast broadcast data, is implemented. The statistical analysis with the time scales of year, month, day, and any search time are provided in this platform. The abnormal alarming information of the background log process system can also be obtained from this platform. After the platform was put into operation, the receiving and monitor efficiency of the downlink data has been improved greatly.