We analyzed the noise characteristics of 0.18μm and 0.35μm nMOSFETs with a gate area of 1.1μm2 in the frequency range of 1Hz to 100kHz. Both two- and four-finger devices were investigated and analyzed. The experimental results show that the noise of 0.35μm gate-length nMOSFET possesses lower 1/f component than the 0.18μm one, whereas the four-finger devices reveal less 1/f noise than those of with two-finger ones. Furthermore, we used time domain measurement of drain current and also the statistical analysis of wafer level on the random telegraph signals (RTS) tests, and the results showed that RTS noise is higher in devices with a 0.35μm gate-length, and devices with a smaller gate finger width produce more RTS noise than devices with a larger gate finger width.