Vapor-liquid equilibrium at 101.3 kPa has been determined for the binary systems ethyl methanoate + 1-bromopropane and ethyl methanoate + cyclohexane and the ternary system ethyl methanoate + 1-bromopropane + cyclohexane. The two binary systems exhibit positive deviations from ideality and the binary ethyl methanoate + cyclohexane has an azeotrope that boils at 325.9 K and contains 82.2 mol % ethyl methanoate. The data were correlated by the Redlich-Kister, Wilson, NRTL, UNIQUAC, and Wisniak-Tamir equations, and the appropriate parameters are reported. The activity coefficients of the ternary system can be predicted from those of the pertinent binary systems. No ternary azeotrope is present.