In the current digital era, the implementation of technology has become one of the strategic steps that can be taken to improve government administration, by utilizing information technology to enhance performance effectiveness and efficiency. The purpose of this research is to assess the effectiveness of the use of E-Office at the Maritime Health Center Office (BKKP), with a focus on the management of assignment letters, incoming letters, and outgoing letters. This research uses a qualitative method with a case study approach, where data were collected through in-depth interviews, observation, and documentation. Data analysis was performed using data reduction, data presentation, and conclusion drawing techniques. The results indicate that the implementation of E-Office at BKKP has had a positive impact by accelerating administrative processes, reducing manual tasks, and improving transparency and data accuracy. Based on Peter Drucker’s theories of efficiency and effectiveness, the research found that E-Office has helped improve efficiency by accelerating document processing and reducing resource usage, but its effectiveness in supporting the achievement of organizational goals is still not optimal. Therefore, there is a need for strategies to strengthen the system, enhance employee training, and simplify bureaucratic procedures, therefore E-Office can be more effective in improving employee performance and supporting the digital transformation at BKKP.