AbstrakPelayanan gizi merupakan bagian integral dari mutu pelayanan rumah sakit karena berperan langsung dalam proses penyembuhan dan keselamatan pasien. Penerapan Sistem Informasi Manajemen Gizi (SIM Gizi) sebagai bagian dari SIMRS diharapkan mampu meningkatkan efisiensi, akurasi, dan koordinasi layanan gizi. Namun, pemanfaatan SIM Gizi tidak selalu berjalan optimal, terutama pada rumah sakit swasta dengan keterbatasan sumber daya. Penelitian ini bertujuan mengevaluasi implementasi SIM Gizi di Rumah Sakit Restu Kasih menggunakan model Human–Organization–Technology Fit (HOT-Fit) serta mengidentifikasi tantangan dan strategi optimalisasi pemanfaatannya. Penelitian ini menggunakan desain evaluatif–eksplanatif dengan pendekatan mixed-methods tipe sequential explanatory. Data kuantitatif dikumpulkan melalui kuesioner kepada pengguna SIM Gizi dan dianalisis menggunakan kerangka HOT-Fit, sedangkan data kualitatif diperoleh melalui wawancara mendalam dan FGD untuk memperdalam pemahaman terhadap temuan kuantitatif. Hasil penelitian menunjukkan bahwa kualitas sistem, kualitas informasi, dan kualitas layanan SIM Gizi berada pada kategori “cukup”. Sistem dinilai stabil dan terintegrasi dengan rekam medis elektronik, namun masih menghadapi kendala pada responsivitas dan pemanfaatan fitur. Faktor organisasi muncul sebagai determinan kunci keberhasilan implementasi. Keselarasan antara dimensi manusia, organisasi, dan teknologi berada pada tingkat moderat dan menghasilkan manfaat bersih yang nyata, tetapi belum optimal. Penelitian ini menyimpulkan bahwa implementasi SIM Gizi di RS Restu Kasih telah berjalan secara fungsional, namun memerlukan penguatan terpadu pada aspek teknologi, sumber daya manusia, dan tata kelola organisasi. Disarankan agar rumah sakit meningkatkan tata kelola SIMRS, pengembangan kompetensi pengguna, serta optimalisasi sistem secara berkelanjutan untuk meningkatkan mutu pelayanan gizi dan efisiensi kerja. Kata kunci: Evaluasi implementasi, Sistem Informasi Manajemen Gizi (SIM Gizi), Rumah sakit, HOT-FitAbstractNutrition services are an integral component of hospital service quality, as they directly contribute to patient recovery, safety, and clinical outcomes. The implementation of a Nutrition Management Information System (SIM Gizi) as part of the Hospital Management Information System (HMIS) is expected to improve efficiency, accuracy, and coordination of nutrition services. However, the utilization of SIM Gizi has not always been optimal, particularly in private hospitals with limited resources. This study aims to evaluate the implementation of SIM Gizi at Restu Kasih Hospital using the Human–Organization–Technology Fit (HOT-Fit) model and to identify the challenges and optimization strategies for its utilization.This study employed an evaluative–explanatory design with a mixed-methods approach using a sequential explanatory strategy. Quantitative data were collected through questionnaires administered to SIM Gizi users and analyzed based on the HOT-Fit framework, while qualitative data were obtained through in-depth interviews and focus group discussions to further explain the quantitative findings.The results indicate that system quality, information quality, and service quality of SIM Gizi are at a “moderate” level. The system is perceived as stable and integrated with electronic medical records; however, challenges remain in system responsiveness and feature utilization. Organizational factors emerged as a key determinant of implementation success. The alignment among human, organizational, and technological dimensions was found to be moderate, resulting in tangible net benefits that have not yet been fully optimized.This study concludes that the implementation of SIM Gizi at Restu Kasih Hospital is functionally adequate but requires integrated improvements in technology, human resources, and organizational governance. It is recommended that hospitals strengthen HMIS governance, enhance user competencies, and continuously optimize the system to improve nutrition service quality and work efficiency. Keywords: Implementation evaluation, Nutrition Management Information System (SIM Gizi), Hospital, HOT-Fit