This paper presents a new Post Distortion Cancellation (PDC) Gilbert-mixer for Ku-band applications to minimize the third-order nonlinear current of transconductance transistors. To illustrate the effectiveness of this scheme, distortion analysis using Volterra series is given. An extra inductor is added between source nodes of switching transistors to decrease the deteriorating effect of parasitic capacitances. The proposed mixer has been simulated in a 0.18-µm RF-CMOS technology and consumes only 6-mW from a 1.8-V supply. Compared to conventional Gilbert-mixer, it typically improves IIP3 by 4.2dB, power conversion gain by 1.1dB and noise figure by 1.4dB.