Osteoartritis (OA) adalah penyakit degeneratif kartilago sendi. Beberapa peresepan obat anti-inflamasi non steroid (OAINS) sebagai terapi farmakologi OA ditemukan masih belum tepat. Studi pendahulu di RS Wolter Monginsidi Manado tahun 2018 memperlihatkan rasionalitas peresepan OAINS OA sebesar tepat indikasi 100%, tepat dosis 77%, dan tepat obat 89%. Hal ini memperlihatkan rasionalitas peresepan masih irasional. Peresepan irasional berpotensi mengakibatkan efek samping atau kejadian masalah terkait obat. Oleh karena itu, diperlukan penelitian mengenai rasionalitas peresepan OAINS pada OA genu lutut untuk mengetahui gambaran karakteristik dan rasionalitas peresepan. Studi potong lintang ini dilakukan secara total sampling yang menggunakan 108 rekam medis periode Januari 2020-April 2021 di Klinik Bina Sehat Semarang kemudian dianalisis secara univariat. Pada hasil penelitian, didapatkan karakteristik pasien adalah 74,1 perempuan, 47,2 % kelompok obesitas, dan 41,7% mengalami derajat nyeri berat. Pada rasionalitas peresepan OAINS adalah tepat diganosis 95,4%, tepat obat 100%, tepat dosis 97,2%, dan tepat indikasi 99,1% dengan kejadian efek samping peresepan OAINS sebesar 1,9%. / Osteoarthritis (OA) is a degenerative disease of joint cartilage. The prescribing of non-steroidal anti-inflammatory drugs (NSAIDs) as pharmacological therapy for OA was found to be imprecise. In 2018, the rationality of NSAIDs prescription at Wolter Monginsidi Hospital, Manado showed as much as 100% proper indication, 77% proper dose, and 89% proper medication. This shows that the rationality of NSAIDs prescription is still irrational. Irrational prescription has the potential to result in side effects or the incidence of drug-related problems. Therefore, it is necessary to determine the rationality and the characteristics of prescribing NSAIDs in elderly knee OA. This cross-sectional study was conducted using a total sampling of 108 medical records for the period January 2020-April 2021 at Bina Sehat Clinic, Semarang which was then analyzed by univariate. In the results of the study, the characteristics of elderly knee OA patients were 74,1% women, 47,2% belonging to obese group, and 47,1% experiencing severe pain. The rationality of NSAIDs prescription was 95.4% proper diagnosis, 100% proper drug, 97.2% proper dose, and 99.1% proper indication with the incidence of side effects of NSAIDs prescribing was 1.9%.