In this report, a broad band (15 GHz to 34 GHz) low noise amplifier using 100 nm GaN on silicon technology is designed and fabricated. The LNA shows an extremely low noise figure of 1.2 dB and small signal gain of 18.5±1.5 dB across the bandwidth. The LNA can work in the drain bias from 3.5 V to 8 V without increasing the noise figure. The chip size is 2 mm × 1.3 mm. The robustness of the LNA is also tested by stressing the working LNA with a continuous-wave input power, no significant degradation is observed.