Abstract: A portable online monitoring system based on Internet was designed for small and medium rotating machinery. The system design was made up of local and remote systems. The data monitored by the local system was collected and processed by LabVIEW software after parameter tuning，the SQL Server database management system was formed，the local data was released by DataSocket technology and B/S networking mode，the remote users could monitor the corresponding remote running state according to their needs. At the same time，it needed to consider network security and permissions settings. Through the experiment，it was proved that the system could realize fast change signal simulating and slow change signal simulating for one second with eight channels，and the fault channel was displayed by optical alarm，sound alarm and pop-up alarm dialog box，which could store and monitor the fault channel. It could realize the data storage and recall of the instant library，the hour library，the day library，the month library and the fault database，and could analyze fault data and real-time data to achieve remote real-time monitoring，analysis and interaction.

Key words: rotating machinery, state monitoring, Internet, LabVIEW, SQL Server