Growing number of passenger in the world resulted congestion problem in the airport. Many airports try to improve the performance of the service by company program related to passenger satisfaction. To develop the company program, management of airport should know performance of existing system. In this research, we measure and compare the performance of the existing system and new system of airport departure terminal of Soekarno-Hatta International Airport (SHIA). Discrete-event simulation method was developed to measure the system. ProModel simulator software, from ProModel Corporation, was utilized to simulate the existing system and new system of Departure Terminal in the Airport. To measure the performance, authors focus on some indicators, i.e., passengers processing time, passengers waiting time, and utilization of each station. The authors make some scenarios based on the increasing of passengers 4.9 % in 2015, 18.9 % in 2020, 17.7 % in 2025, and 1.5 % in 2030. There is a significant difference in 2020–2025 in amount of 25 % in order to the passengers’ average time. Therefore, the new system will have better performance.