This paper demonstrates a fully integrated W-band frequency multiplier chain, which is implemented in 0.15-µm GaAs mHEMT process. The frequency multiplier chain includes a passive balanced doubler, a resistive feedback buffer amplifier, and an anti-parallel diode pair wideband tripler. It has a 6-dB bandwidth of 45% (72–114 GHz) with a peak conversion gain of −17.9 dB, and dc consumption of 120 mW. To the authors' best knowledge, this is the first fully integrated frequency multiplier chain of W-band in commercial mHEMT process.