The first antimonide-based compound semiconductor (ABCS) MMIC, a Ka-Band low-noise amplifier using 0.25-μm gate length InAs/AlSb metamorphic HEMTs, has been fabricated and characterized on a 75 μm GaAs substrate. The compact 1.1 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> three-stage Ka-band LNA demonstrated an average of 2.1 dB noise-figure between 34-36 GHz with an associated gain of 22 dB. The measured dc power dissipation of the ABCS LNA was an ultra-low 1.5 mW per stage, or 4.5 mW total. This is less than one-tenth the dc power dissipation of a typical equivalent InGaAs/AlGaAs/GaAs HEMT LNA. Operation with degraded gain and noise figure at 1.1 mW total dc power dissipation is also verified. These results demonstrate the outstanding potential of ABCS HEMT technology for mobile and space-based millimeter-wave applications.