A millimeter-wave dual-wideband low noise amplifier (LNA) was designed. It could reconfigure the passive inductors through RF switches, so that it could operate at the center frequencies of 28 GHz and 32 GHz, respectively, and is suitable for millimeter-wave 5G communications. The reconfigurable low noise amplifier (RLNA) has been designed in a 55-nm CMOS process. The post-simulation results show that, with a switch voltage (Vs) of 0 V, the RLNA has a gain of 23 dB, an input 1 dB compression point (IP1dB) of -5.4 dBm at the center frequency of 28 GHz, and a noise figure of 4.1-4.4 dB over -3-dB bandwidth from 26.1-32.2 GHz (6.1 GHz). While with a Vs of 1.2 V, the RLNA achieves a gain of 20 dB, an IP1dB of -7.5 dBm at the center frequency of 32 GHz, and a noise figure of 4.4-4.7 dB over -3-dB bandwidth from 28-34 GHz (6 GHz). The chip has an area of 0.70×0.55 mm² and consumes 25.2 mW at a supply voltage of 1.2 V.