Kacang kedelai (Glycine max L. Merr) memiliki kemampuan untuk mencegah terjadinya kerusakanginjal akibat keracunan diazinon karena mengandung tannin, proanthocyanidin, dan isoflavonoid. Tujuanpenelitian ini untuk membuktikan efek pemberian tepung kedelai sebagai nefroprotektor terhadap tikus yangdiinduksi diazinon. Penelitian dilakukan di Laboratorium Fisiologi dan Farmakologi Fakultas KedokteranUniversitas Jember, pada bulan Oktober-Desember 2017. Sebanyak 25 tikus wistar jantan usia 12-15 minggudiacak dan dibagi menjadi 5 kelompok, kelompok kontrol normal (K1) yang diberikan normal salin selama28 hari, kelompok kontrol negatif (K2) yang diberikan normal salin 28 hari dan diazinon selama 5 hari.Kelompok perlakuan yang diberikan larutan tepung kedelai dengan dosis masing-masing (K3) 1 g/10mL,(K4) 1,5 g/10mL, dan (K5) 2 g/10mL selama 28 hari, dilanjutkan diazinon 40 mg/kgBB selama 5 hari. Tikusdisakrifasi menggunakan eter kemudian diambil organ ginjal dan dibuat preparat histopatologi yang diwarnaiHematoksilin-Eosin. Pengamatan berat ringan kerusakan ginjal dinilai berdasarkan skoring yang dikonversimenjadi data interval menggunakan method of successive interval (MSI). Kelompok K1 memiliki rata-rataskor histopatologi terendah yaitu 2,427±0,191, sedangkan rata-rata skor histopatologi tertinggi di kelompokK2 4,272±0,221. Kelompok perlakuan dengan rata-rata skor histopatologi terendah berada pada kelompokK5 yaitu 2,875±0,211. Terdapat perbedaan signifikan terhadap rata-rata skor histopatologi ginjal tikusantarkelompok (Tukey HSD, p Kata kunci: tepung kedelai, diazinon, tikus wistar, kerusakan ginjal. The Effect of Soybean Flour Administration to Renal Histopathology of Diazinon-Induced Wistar Rats Abstract Soybean (Glycine max L. Merr) has the ability to prevent renal injury due to diazinon intoxicationwhich contains tannin, proanthocyanidin, and isoflavonoid. This study was intended to prove the effect ofsoybean flour administration as nephroprotective agent on diazinon induced rats. This study was conductedat Physiology and Pharmacology Laboratory, Faculty of Medicine Universitas Jember on October-December2017. A total of 25 male wistar rats, aged 12 – 15 months were randomized and divided into 5 groups, normalcontrol group (C1) which was given normal saline solution for 28 days, negative control group (C2) which wasgiven diazinon for 5 days and normal saline solution for 28 days. The treated group was given soybean floursolution with 3 different dosages, 1g/10 ml (C3), 1.5 g/10 ml (C4), and 2g/10 ml (C5) for 28 days, continuedwith diazinon administration of 40 mg/kg for 5 days. Rats euthanasia were done using ether, followed bykidney extraction and its histopathology preparation stained by Hematoxylin Eosin. The observation ofrenal injury severity was assessed by a scoring converted into interval data by using method of successiveinternal (MSI). C1 group had the lowest mean histopathology score 2.427±0.191 whereas the highest meanhistopathology score was on group C2 4.272±0.221. The treated group with the lowest mean histopathologyscore was on group C5 2.875±0.211. There was a significant difference of mean kidney histopathologicalscores between groups (Turkey HSD, p Keywords: soybean flour, diazinon, wistar rats, renal injury.