Vapor-liquid equilibrium at 94 kPa has been determined for the binary systems of methyl 1,1-dimethylethyl ether (MTBE) + 1,3-dioxolane and methyl 1,1-dimethylethyl ether + 2,2’-oxybis[propane] (diisopropylether). The binary system with 1,3-dioxolane deviates moderately from ideal behavior, and the system with 2,2’-oxybis[propane] behaves almost ideally; neither system presents an azeotrope. The activity coefficients and boiling points of the binary system methyl 1,1-dimethylethyl ether + 1,3-dioxolane were well correlated with its composition by the Redlich-Kister, Wohl, Wilson, UNIQUAC, NRTL, and Wisniak-Tamir equations.