This letter presents a design methodology for the millimeter wave amplifier using 90-nm Taiwan Semiconductor Manufacture Company (TSMC) CMOS technology. The proposed design scheme with mathematically modeled transmission lines and interstage matching transformers illustrates how to design a millimeter amplifier considered in the maximum power transfer. The single-ended transformer-coupled CMOS PA is implemented to verify the design methodology. The design consists of neutralized common source (CS) amplifiers, matching transmission lines, and 3D modeled transformers. The designed circuit shows 16.2-dB gain and 9-dBm saturation power over 60-GHz channel. The measured results are well matched with the proposed modeling results. (C) 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:506-509, 2011; View this article online at wileyoninelbrary.com. DOI 10.1002/mop.25782