The pocket implantation effect on drain current flicker noise in 0.13 μm CMOS process based high performance analog nMOSFETs is investigated. Our result shows that pocket implantation will significantly degrade device low-frequency noise primarily because of nonuniform threshold voltage distribution along the channel. An analytical flicker noise model to account for a pocket doping effect is proposed. In our model, the local threshold voltage and the width of the pocket implant region are extracted from the measured reverse short-channel effect, and the oxide trap density is extracted from a long-channel device. Good agreement between our model and the measurement result is obtained without other fitting parameters.