Abstract: A six-stage gas switch with low inductance developed for fast linear transformer drivers (LTDs) is described, and the inductance of the switch with single channel and multi-channel discharges is investigated. The measured inductance ofthe switch with single channel discharge is consistent with the calculated results by the Nagaokas equation. It is affected by both the circuit loop area and the electrode azimuthal current. The triggered multi-stage switch with multi-channel discharges has the lowest inductance of 49 nH that is 4 nH more than that of the same sized cylinder, indicating that the azimuthal current along toroidal electrodes has little contribution to the inductance of the switch in practical operation.