The spread of diseases caused by mosquito bites can be overcome by providing larvicides in water reservoirs. Avocado seed extract has been proven as a natural larvicide. The purpose of this study was to evaluate the effect of avocado seed extract concentration on the physical characteristics of sand granules and the mortality of mosquito larvae. Sand granules were made using the wet granulation method with extract concentrations of 1% (F1) and 2% (F2). Tests included organoleptic, water content, particle size distribution, flow time, flow rate, angle of repose, and dissolution time. The treatment group was Abate® positive control, tap water negative control, 37.5 mg extract, 75 mg extract, 6 preparations from FI and FII with variations in the amount of sand granules of 1.25 g, 2.5 g, and 3.75 g. The organoleptic results were granules, cream-colored, and odorless. The dominant particle distribution was 250 µm. The water content of both formulas was 2.29%, flow time was 1.92 and 1.87 seconds; Flow rates of 53.47 and 54.55 g/s, angle of repose of 30.22° and 30.06°. Dissolution time of 63.47 and 64.93 seconds. Mortality of negative control larvae was 0%, positive control and 75 mg extract had the same results, namely 100%, 37.5 mg extract and 3.75 grams of FII granules were > 80%, the other groups ranged from 20.5 to 76.9%. The results of statistical analysis stated that the concentration of avocado seed extract did not affect the physical characteristics of sand granules. The concentration of extract and the number of sand granules affected the mortality of mosquito larvae. ABSTRAK Penyebaran penyakit karena gigitan nyamuk dapat diatasi dengan memberikan larvasida di penampungan air. Ekstrak biji alpukat telah terbukti sebagai larvasida alami. Tujuan penelitian mengevaluasi pengaruh konsentrasi ekstrak biji alpukat terhadap karakteristik fisik sand granules dan mortalitas larva nyamuk. Pembuatan sand granules menggunakan metode granulasi basah dengan konsentrasi ekstrak 1% (F1) dan 2% (F2). Pengujian meliputi organoleptis, kadar air, distribusi ukuran partikel, waktu alir, kecepatan alir, sudut istirahat, waktu melarut. Kelompok perlakukan kontrol positif Abate®, kontrol negatif air ledeng, ekstrak 37,5 mg, ekstrak 75 mg, 6 sediaan dari FI dan FII dengan variasi jumlah sand granules sebesar 1,25 g, 2,5 g, dan 3,75 g. Hasil organoleptis berbentuk granul, berwarna krem, dan tidak berbau. Distribusi partikel dominan berukuran 250 µm. Kadar air kedua formula 2,29%, waktu alir 1,92 dan 1,87 detik; kecepatan alir 53,47 dan 54,55 g/s, sudut istirahat 30,22° dan 30,06°. Waktu melarut 63,47 dan 64,93 detik. Mortalitas larva kontrol negatif 0%, kontrol positif dan ekstrak 75 mg hasilnya sama yaitu 100%, ekstrak 37,5 mg dan granul FII 3,75 gram > 80%, kelompok yang lain berkisar 20,5-76,9%. Hasil analisis statistik menyatakan konsentrasi ekstrak biji alpukat tidak berpengaruh terhadap karakteristik fisik sand granules. Konsentrasi ekstrak dan jumlah sand granules berpengaruh pada mortalitas larva nyamuk.