The usage of ethanol (EtOH)-blended gasoline (gasohol), has been increasing in recent years. EtOH has influence on the distribution and biodegradation of aromatic compounds such as BTEX (benzene (B), toluene (T), ethylbenzene (B), and xylene (X)) that are gasoline compositions. In this study, the effect of EtOH on the aerobic biodegradation of B, T and E was investigated using a BTEX and EtOH-degrading bacterium, Rhodococcus sp. EH831. The degradation rates of B in the conditions of 1:1, 1:4, and 1:0.25 mixtures with EtOH (B:EtOH, mol:mol) were ranged from $3.82{pm}0.20$ to $5.00{pm}0.37{mu}mol{cdot}g-dry$ cell wight $(DCW)^{-1}{cdot}h^{-1}$. The degradation rate of T was the fastest in the 1:0.25 mixture ($6.63{pm}0.06{mu}mol{cdot}g-DCW^{-1}{cdot}h^{-1}$), and it was the lowest in the 1:4 mixture ($4.41{pm}0.04{mu}mol{cdot}DCW^{-1}{cdot}h^{-1}$). The degradation rates of E were increased with increasing the addition amount of EtOH: The degradation rate of E was the highest in the 1:4 mixture ($1.60{pm}0.03{mu}mol{cdot}g-DCW^{-1}{cdot}h^{-1}$), and the rates were $1.42{pm}0.06$, $1.30{pm}0.01$, and $1.01{pm}0.30{mu}mol{cdot}g-DCW^{-1}{cdot}h^{-1}$ in the 1:1, 1:0.25, 1.0 mixtures, respectively. In conclusion, the biodegradation of B, T, E by Rhodococcus sp. EH831 was not significantly inhibited by the co-existence of EtOH.