ABSTRAK Peradangan pada obesitas dapat menyebabkan peningkatan sitokin pro-inflamasi sehingga memicu hipertrofi kerusakan pada tubulus ginjal. Pemberian metformin pada penderita obesitas dapat menurunkan produksi sitokin pro-inflamasi dan mencegah terjadinya kerusakan ginjal. Penelitian ini bertujuan mengetahui efek metformin terhadap berat badan dan gambaran histopatologi ginjal pada tikus model obesitas. Penelitian eksperimental dengan rancangan posttest only controlled group design dengan pendekatan kualitatif dan kuantitatif, menggunakan tikus putih galur Wistar jantan, usia 10-12 minggu, berat badan (BB) 200-250 gram, berjumlah 15 ekor. Tikus dibagi dalam 3 kelompok perlakuan; K1: kontrol normal; K2: kontrol negatif (model obesitas); K3: model obesitas + terapi metformin 250 mg/kgBB. Tikus dimodifikasi menjadi model obesitas dengan pemberian high fat diet (HFD). Dilakukan pengukuran BB secara berkala. Gambaran histopatologi ginjal didapatkan dari blok parafin dengan pewarnaan Hematoksilin eosin (HE) dan dianalisis secara kualitatif dengan menilai tingkat kerusakan tubulus ginjal dan analisis kuantitatif dilakukan dengan Grapphad Prsima 8.0.0 menggunakan uji nonparametrik Kruskal-Walis. Hasil terapi metformin menurunkan berat badan pada K3 mulai hari ke-42 (p=0,0049). Skor cedera tubulus ginjal lebih rendah dibandingkan K2, namun tidak berbeda secara statistik (p=0,9). Metformin mampu menurunkan berat badan dan mencegah kerusakan tubulus ginjal tikus model obesitas. ABSTRACT Obesity is a chronic disease resulting from the accumulation of excess body fat. Obesity can lead to an increase in pro-inflammatory cytokines that can cause injury of kidney tubule. Giving metformin to obese can reduce the production of pro-inflammatory cytokines and prevent the occurrence of tubule injury. The aim of this study to determine the effect of metformin on body weight and kidney histopathological of obese rat model. This is a experimental research with posttest only controlled group design with qualitative and quantitative approaches. This study used 15 male Wistar strain white rats, aged 10-12 weeks, body weight (BB) 200-250 grams. The rats were divided into 3 groups; K1: normal control; K2: negative control (obesity model); K3: obesity model + metformin therapy 250 mg/kgBB. The rats were modified into models of obesity with high fat diet (HFD)administration. Periodic BB measurements are carried out. The histopathological kidney is obtained from the paraffin bloc and Hematoxylin eosin (HE) staining. The data were analyzed qualitatively by assessing the degree of renal tubules injury and quantitative analysis was carried out by assessing the level of kidney damage using Grapphad Prsima 8.0.0 with nonparametric Kruskal-Wallis test. Metformin therapy decrease weight on K3 starting on day 42, (p=0.0049). The renal tubule injury score was lower than K2, but there was not statistically different (p=0,9). Metformin were able to decrease weight and prevent kidney tubule injury in obese rats model