This paper presents a modified post-distortion (PD) linearization technique for cascode common-gate low noise amplifiers (CG-LNAs) working at high frequencies up to millimeter-wave band. This technique utilizes an auxiliary transistor together with an inter-stage inductor to suppress the third order distortion without degrading gain. The input third order intercept point (IIP3) of the linearized CG-LNA is improved by a factor of up to 12 dB. For demonstration, an mm-wave differential CG-LNA was fabricated based on a 65-nm CMOS process. It achieves 2.4–10.6 dBm IIP3, 9.6–12 dB gain, 5.0–5.45 dB NF over 26–31 GHz and consumes 14.4 mW from a 1.2 V supply.