This paper describes the design topology of two-stage ultra-low power low noise amplifier (LNA) using the forward body bias technique for wireless sensor network (WSN) application. The proposed design employs CMOS 0.13-µm technology at 2.4 GHz frequency. The LNA consumes low power from the forward body bias technique at the first and the second stages. The threshold voltage of the transistor can be lowered using the forward body bias technique. Two stages are implemented in order to enhance the gain while obtaining low power consumption for overall circuit. The measurement results show that the LNA consumes a total power of 0.55 mW at supply voltage 0.55 V. The input return loss (S11) and the output return loss (S22) is 10 and 12 dB, respectively. A gain of 12 dB, noise figure (NF) of 5.9 dB and input third-order intercept point (IIP3) of −3 dBm are achieved.