This study examines the role of the FINA accounting information system in improving operational efficiency and sales control at PT Tunas Surya Sentausa. The main issue addressed is the suboptimal integration of systems and interdepartmental procedures. A qualitative case study method was employed, using interviews, observations, and documentation. Findings indicate that FINA enhances process speed and data accuracy, though technical and procedural issues remain. Recommendations include system feature enhancements, workflow integration, and user training.