The present disclosure relates to a data processing apparatus. The data processing apparatus includes: at least one data processor configured to collect the data from the RTUs and check alarm data associated with the collected data; a first data queue generating unit configured to receive the alarm data output from the data processor to create an alarm data queue; an alarm processing unit configured to receive the alarm data included in a first alarm data queue of the first data queue generating unit sequentially to create a second alarm data queue for creating an alarm message, and to create an alarm message based on alarm data in the second alarm data queue to output it. The alarm processing unit includes a second alarm data queue generating unit configured to receive alarm data from the first data queue generating unit and store the received alarm data into a second alarm data queue.