We display important test information from radar, telemetry in real time for monitoring and control of guided missile flight test. Clearing test area is the most important thing for safety. Thus, we have to constantly monitor and control ships around the test area. Several maritime surveillance radars are deployed around the test area for that purpose. However, multiple points are displayed for the same target when using multiple surveillance radars and this confuses the test personnel during the mission. In this paper, we suggested a method to solve this problem by analyzing error factor of surveillance radar and comparing the correlation of each radar data.