Customer satisfaction is strongly influenced by the quality of service provided by the company. The number of requests that exceed the existing capacity can form delay in the system’s queue. Henceforth, we made an observation at the 34.xxx.xxx gas station which is located on one of main street of Depok, West Java, Indonesia. The observation is focused on motorist and Pertalite gas refueling. Duration of the observation is 30 minutes for 5 work days during rush hour after working hours are over, which is at 4.30 pm – 5.00 pm where the customer’s arrival rate increases rapidly. The purpose of this study is to improve the efficiency of gas station services, especially to minimize waiting time and worker utilization. In this case, the researcher uses Arena Simulation software with discrete event simulations at two servers. This research brings two improvement scenarios, to add one additional server, and add one operator to the existing server. As a result, the average waiting time is decreased to 7.58 for the first server and 19.86 for the second server if the gas station adds another server into the system. The first scenario even brings in an 1,04% increase of system productivity level.