Electron transport properties of pristine silicon-substituted analogue of pyrene, Si 16 H 8, and its carbon-doped analogue, Si 14 C 2 H 8, between two semi-infinite aluminum nanochain electrodes were investigated by means of density functional theory plus nonequilibrium green's function method. Here, the current-bias (I–Vb) characteristics were studied in the bias potential range of 0.0 up to 2.0 V in 0.1 V steps by imposing three gate voltages including -3.0, 0.0 and +3.0 V. The considerable result of the present study was the observation of multiple negative differential resistance (NDR) regions, suggesting that the studied systems could be used as nano-multi-switch. The I–Vb behavior of the studied systems along with the observation of the NDR's in each considered gate voltage was interpreted by means of transmission spectrum. These interpretations were carried on by the integration of the transmission spectrum in the corresponding bias window. The observed NDR characteristics including the bias range and current amplitude could be changed by the variations in the applied gate voltage. Controlling NDR characteristics of these devices using the variations of the gate voltage is a major advantage for practical purposes.