Abstract: In view of problems of expensive hardware and higher maintenance cost in standard hot standby scheme of coal mine monitoring and control system, the paper designed a hot standby system with pure software mode. The system uses combinations of file differential backup and MYSQL incremental backup to store data in main and standby computer, that is, using RSYNC file synchronization algorithm to backup file, using Binary Log mechanism of MYSQL database to open a log file, exporting modified data in a period to incremental backup file and sending incremental backup files to standby computer, and the standby computer introduces the data into database, so as to achieve synchronization operation of database. In the same way, modified data in the standby computer was synchronized to the main computer when the main computer has fault. The hot standby system has been applied in coal enterprises and meets with requirements of real-time and completeness of the data in coal mine momitoring and control system.