||With recent advance in CMOS processes, many essential building blocks for wireless transceivers, such as low-noise amplifier (LNA), mixer, frequency synthesizer, channel selection filter and digital-to-analog converter, have been demonstrated using CMOS technology. However, not much work has been done or reported a CMOS power amplifier, in particular at low supply voltage. As supply voltage is reduced to 1V, the performance of the power amplifier, such as the output power and the efficiency are degraded. In this thesis, the design considerations of a RF CMOS power amplifier under low supply voltage are detailed. A two-stage power amplifier operated at 2.4GHz and 1-V supply has been designed and fabricated for Bluetooth applications in a standard 0.35μm CMOS technology. A common-gate Class E output stage, which operates under low supply voltage without degrading the efficiency, is proposed. A pre-amplifier with positive feedback configuration is employed to drive the common-gate output stage. To achieve high efficiency and high output power, bondwires are used as inductors for the power amplifier because of their high quality factor. Measurement results show that the amplifier delivers 18dBm output power with 33% power-added efficiency (PAE) under a 1V supply voltage. With a 1.2V supply, the amplifier delivers 20dBm output power with 35 % PAE and can be integrated for class 1 Bluetooth application. The measured output spectrum falls within the Bluetooth spectrum mask when a modulated signal is input to the power amplifier. The adjacent-channel power rejection (ACPR) at 550kHz offset is -21.4 dBc under 1V and -23.5 dBc with 1.2V supply voltage.