The high-pressure vapor-liquid equilibria of butane/ethanol system and isobutane/ethanol system were measured by a minimum continuous flow method using a process gas chromatography at 313-403 K. Experimental PXY data were compared with references. The modified RK EOS parameters were regressed and PXY data were also compared with PERK EOS. (C) 2014 Elsevier B.V. All rights reserved.