Inventory days atau pola perputaran persediaan ialah suatu cara untuk memantau pola perputaran stok perbekalan farmasi dengan baik. Tujuan penelitian ini untuk menggambarkan pola perputaran perbekalan farmasi periode 1 Januari–31 Maret 2021 di Rumah Sakit “X” Jakarta Selatan. Sampel diambil secara random sebanyak 335 item dengan menggunakan rumus randbetween pada Ms. Excell. Data obat yang akan diolah diambil setiap akhir bulan berupa data penjualan, data sisa stok terakhir dan data rata-rata konsumsi. inventory days dihitung dengan membagi jumlah stok akhir dengan jumlah rata-rata konsumsi. Setelah didapatkan hasil perhitungan inventory days dari 335 item obat, kemudian dibuat klasifikasi very fast moving, fast moving, slow moving, not moving dan obosolete dan VEN disajikan dengan bentuk tabel dan grafik. Hasil yang didapat yaitu perputaran obat Inventory days <30 hari yang paling banyak yaitu kelompok very fast moving bulan Maret 26 item, fast moving bulan Maret 47 item, slow moving bulan Maret 10 item. Perputaran obat inventory days >30 hari not moving stabil 12 item dan obsolete 7 item. Perputaran obat inventory days <30 hari paling banyak kelompok obat vital pada bulan Februari dan Maret sebanyak 28,13%. Perpuratan obat inventory days >30 hari paling banyak kelompok obat essensial pada bulan Januari sebanyak 92,2%/Inventory days or inventory turnover patterns are a way to properly monitor the turnover pattern of pharmaceutical supplies. The purpose of this study was to describe the pattern of pharmaceutical supply turnover for the period January 1, 2021 - March 31, 2021 at the "X" Hospital, South Jakarta. Samples were taken randomly as many as 335 items using the randbetween formula on Ms. Excel. Drug data to be processed is taken at the end of each month in the form of sales data, last remaining stock data and average consumption data. Inventory days are calculated by dividing the amount of ending stock by the average amount of consumption. After getting the results from the calculation of Inventory days of 335 drug items, then the classification of very fast moving, fast moving, slow moving, not moving and obosolete and VEN is made in the form of tables and graphs. The results obtained are drug turnover in Inventory days <30 days with the most groups being very fast moving in March 26 items, fast moving in March 47 items, slow moving in March 10 items. Drug turnover Inventory days >30 days not moving stable 12 items and obsolete 7 items. Inventory days <30 days drug turnover was the most in the vital drug group in February and March as much as 28.13%. Inventory days >30 days most of the essential drugs group was in January as much as 92.2%