A 2.4-6 GHz broadband CMOS differential LNA for WLAN and UWB receiver is presented. The LNA is fabricated with the 0.18 μm 1P6M standard CMOS process. Measurement of the chip is performed on a FR-4 PCB test fixture. In the UWB low-band (3 to 5.15GHz), the broadband LNA exhibit a gain of 17.5-18.2 dB, noise figure of 3.4-5dB, input/output return loss better than 10 dB, and input P 1dB of -17 dBm, respectively. In the band from 2.4 to 3GHz (covering a 802.11b/g band), the LNA exhibit a gain of 17.5-18dB and noise figure less than 3.5dB. From 5.2 to 6GHz, the noise figure of the LNA becomes higher than 5 dB. The gain also decrease to about 15 dB. The DC supply is 1.8V.