Today, hydrophobic eutectic solvents are promising extractants for metal ions. Their main advantage is the "adjustability" of their physicochemical and extraction properties due to a wide range of compounds suitable for preparation. In this study, eutectic solvents based on octanoic acid and aliphatic alcohols (1-decanol, 1,9-nonanediol, geraniol, linalool) will be investigated for the extraction of Fe(III) ions, which are often present in various mixtures, such as wastewater, leaching solutions of lithium iron phosphate batteries, etc. The octanoic acid/alcohol ratio in eutectic solvents was 1/1. The ratio of aqueous and organic phases during extraction was also 1/1. The Fe(III) distribution coefficient was calculated as the ratio of the equilibrium concentration of Fe(III) ions in the eutectic solvent phase to the equilibrium concentration of Fe(III) ions in the aqueous phase. It was found that with an increase in the pH of the initial solution from 1.4 to 2.4, the Fe(III) distribution coefficient increased. In addition, the extraction efficiency depends on the aliphatic alcohol and increases in the following series: linalool, 1,9-nonanediol, geraniol, 1-decanol. The distribution coefficients at pH 2 were 0.95, 1.36, 1.69, 2.07, respectively. The results indicate that the structure of the aliphatic alcohol affects the extraction capacity of octanoic acid. The reason for this may be multiple hydrogen bonds and Van der Waals interactions between the components, which may hinder the extraction of Fe(III) ions due to steric hindrance. For example, linalool is a tertiary alcohol, which may be the reason for the formation of multiple interactions between the components of the eutectic solvent and, as a result, the reason for the lowest extraction capacity.