In this letter we describe the fabrication of enhancement-mode MISFETs on InGaAs grown by liquid-phase epitaxy (LPE) using an anodic Al2O3/anodic native oxide double layer as a gate insulator. The normally-off device of 10 μm gate length shows the effective channel mobility of 1400 cm2/Vs. The interface state density distribution of this double-layer MIS of InGaAs is also reported. The density of 2 × 1013 cm−2 eV−1 at Ec −0.057 eV and the minimum of 8 × 1011 cm−2 eV−1 near midgap are measured from C/V characteristics.