A two-stage common-source (CS) low-noise amplifier (LNA) that uses a forward-body-bias technique in N-type metal–oxide semiconductor devices and intended to achieve a high gain and low power consumption is proposed in this study for ultra-wideband (UWB) applications. Its first stage yields an exceptionally high gain because of high transconductance (gm1 = 16 mS) of the input device. It also shows simultaneous wideband input matching and low-noise figure (NF) characteristics with the aid of source degenerated inductors. A simple source degenerated CS topology with the shunt-peaking inductor Ld2 is designed as the second stage to enhance the gain response at high frequencies. Using a standard 90 nm complementary metal–oxide semiconductor process, the proposed UWB LNA achieves a gain S21 ≥ 20 dB in the frequency range of 3.1–10.6 GHz, while consuming only 12.6 mW power from a 0.6 V supply voltage. The simulation results show a minimum NF (NFmin) below 1.7 dB in the frequency range of 3.1–10.6 GHz and input return loss S11 < −10 dB in the frequency range of 3.5–10 GHz. When a two tone test is performed with a frequency spacing of 2 MHz, a high value of third-order input intercept point of −8 dBm is also achieved.