High-mobility In0.6Ga0.4As channel metal oxide semiconductor high electron mobility transistor (MOSHEMT) and metal oxide semiconductor field effect transistor (MOSFET) are investigated based on simulation and experiment in this paper. It is found that InAlAs barrier layer has a great influence on the characteristics of In0.6Ga0.4As MOSHEMT. In0.6Ga0.4As MOSHEMT exhibits excellent electrical characteristics compared with In0.6Ga0.4As MOSFET. The experimental results show that the effective channel mobility of MOSHEMT is 2812 cm2/V·s-1, which is 3.2 times that of MOSFET. A 0.02 mm gate length MOSHEMT shows higher drive current, peak transconductance, Ion/Ioff ratio and gate breakdown voltage and lower sub-threshold swing than the MOSFET with the same gate length.