We report the preparation of InGaAs/AlGaAs strained‐layer(pseudomorphic) modulation‐doped field‐effect transistor (MODFET) structures by organometallic vapor phase epitaxy (OMVPE). Devices fabricated from these structures with 0.9 &mgr;m gate lengths had dc extrinsic transconductances up to 340 mS/mm. Microwave testing up to 40 GHz showed current gain cutoff frequencies ( fT) of 22 GHz and estimated maximum frequency of oscillation ( fmax) of 70 GHz. This is the first report to our knowledge of the use of OMVPE material in the fabrication of pseudomorphic MODFETs.