A discrete low noise In 0.6Ga 0.4As MHEMT device with 150 nm gate length was flip-chip assembled on the low-cost RO3210 organic substrate for wireless communication applications. The measured DC characteristics were very similar before and after flip-chip assembly. The flip-chip packaged MHEMT device showed a high drain current density of 516 mA/mm and a maximum transconductance of 576 mS/mm at a V DS of 0.8 V. The insertion gain of the flip-chip packaged device was decayed less than 2 dB up to 100 GHz as compared to the data of bare die. Moreover, the measured minimum noise figure was less than 2 dB as measured at V Ds of 0.7 V and V Gs of -0.7 V in the frequency range from 20 to 64 GHz for the device after flip-chip assembly. The excellent performance of the flip-chip packaged MHEMT device demonstrates the feasibility of using low cost organic substrate for high frequency applications up to W band.