In this work, a V-band low noise amplifier (LNA) is developed in a commercial 0.13µm RFCMOS technology. Common-source (CS) topology, known to show a better noise performance than the cascode topology, was adopted and 4-stage was employed to achieve a sufficient gain at the target frequency near the cutoff frequency f_T. The measured gain was 18.6dB with V_DD=1.2V and increased up to 20.2dB with V_DD=1.8V at 66GHz. The measured NF showed a minimum value of 7.0dB at 62GHz. DC power consumption was 24mW with V_DD=1.2V. The size of the fabricated circuit is as compact as 0.45mm × 0.69mm. This work was further extended to investigate the effect of dummy fills on LNA performance. An identical LNA, except for the dummy fills formed very close to (and under) the metal lines of spiral inductors and interconnects, was also fabricated and compared with the standard LNA. A peak gain degradation of 3.6dB and average NF degradation of 1.3dB were observed, which can be ascribed to the increased mismatch and line loss due to the dummy fills.