Electrical properties of GaN-based heterostructures adopting InAIN/AlGaN bilayer barriers are investigated by Hall-effect and current voltage measurements. It is found that this structure possesses both merits of high two-dimensional electron gas (2DEG) density and low gate leakage current density, while maintaining high 2DEG mobility. Furthermore, temperature dependence of the 2DEG density in this structure is verified to follow a combined tendency of InAIN/GaN (increase) and AlGaN/GaN (decrease) heterostructures with increasing temperature from 90 K to 400 K, which is mainly caused by superposition of the effects from carrier thermal activation induced by extrinsic factors in InAIN layer and the reduced conduction-band discontinuity. (C) 2016 Elsevier B.V. All rights reserved.