In one disclosed embodiment, the present test structure for determining gate-to-body current in a floating body FET includes a floating body FET situated over a semiconductor layer, where the floating body FET includes a first gate and first and second source/drain regions. The floating body test structure further includes a second gate and a first contact situated over the first source/drain region. A gate-to-channel current measured between the second gate and the first contact is utilized to determine the gate-to-body tunneling current. The gate-to-body tunneling current can be determined by subtracting the gate-to-channel current from twice a source/drain current of the floating body FET. The test structure may also include a second contact situated on a doped region in the semiconductor layer, where a diode current flow through the doped region determines a body voltage for the floating body FET.