The Point of Sale application as one of the main auxiliary systems for retail companies that can increase sales and work efficiency, makes the need for an application system work well and can be done by anyone with the right training. The usability test conducted on the Retail Pro 8 system to prove how the system that has been used for more than 10 years by Gajahmada Supermarket helps employees to work effectively. With the Heuristic approach by Jakob Nielsen which explains 5 Usability for a system Efficiency, Learnability, Memorability, error and satisfaction are in the Retail Pro 8 system. The Usability value obtained with the PSSUQ questionnaire gets a good usability score of 3.86 with the heuristic evaluation test which only gets 2 problems that are commonly received by ordinary users using the Point of Sale Retail Pro 8 system.