The first results concerning dual-gate AlGaN/GaN MODFETs are presented. The devices have 0.65 μm gate lengths and were grown by metal organic chemical vapour deposition (MOCVD) on a sapphire substrate. The continuous wave (CW) output power is in excess of 2.5 W/mm at 4 GHz. The corresponding large-signal gain is 11.5 dB and the power added efficiency is 30.6%. Dual-gate devices with different gate lengths can provide simultaneous high breakdown voltage and high current-gain cutoff frequency for the broadband power amplifiers.