Gelatin is one type of protein derived from natural collagen found within the skin, bones, and connective tissue of animals. This study, used eel (Anguilla marmorata (Q) Gaimard) fish skin as the material for gelatin which was extracted using acetic acid solution of 3%, 6% and 9% for 48 hours. This study aims at determining the concentration of acetic acid towards the yield value and the quality (organoleptic, water content, ash content, and arsenic content) in accordance with Indonesian National Standards. The method used to determine the water content is oven method, to determine ash content is muffle furnace method, to determine arsenic metal is Atomic Absorption Spectrophotometry (SSA) and to find out the gelatin functional groups is FTIR (Fourier Transform Infrared) spectroscopy. The result shows that the gelatin extracted using 3% acetic acid has the highest yield value of 18.2% and for the quality of gelatin concentration of 9% acetic acid is the most optimal concentration with yellowish gelatin color, odorless and flavorless, and has water content of 7.099%, ash content of 0.96% and arsenic content of <0.01mg / kg. The result of characterization using FTIR shows that sample obtained by characterization of functional group smiliar to gelatin.