The low-frequency noise (LFN) characteristics of a vertical pillar-type FET were investigated in order to observe the different influences of the source resistance ( $R_{S})$ and the drain resistance ( $R_{D})$ . Because of its inherent vertical channel structure, the $R_{S}$ and $R_{D}$ are inevitably different. To observe the effects of the asymmetric $R_{S}$ and $R_{D}$ on LFN, a forward mode (FM) and reverse mode (RM) of voltage sweep were used. In the RM, the correlated mobility fluctuation effect was higher and the power spectral density of resistance fluctuation ( $S_{\mathrm{ RSD}})$ was lower than those in the FM. In addition, $S_{\mathrm{ RSD}}$ was correlated with the $R_{S}$ , but little with the $R_{D}$ . To suppress $S_{\mathrm{ RSD}}$ , it is important to minimize the $R_{S}$ .