In this work, we investigate the humidity-sensing performance on a humidity-sensitive p-channel field effect transistor (FET) having a floating-gate (FG) and a control-gate (CG) placing horizontally each other. A sensing layer is formed onto a part of the CG and the O/N/O stack over the FG by inkjet-printing process. The printed ink is composed of indium oxide (In₂O₃. nanoparticles and dimethylformamide (HCON(CH₃)₂) as solvent. DC/Pulsed measurements are carried out by switching chamber ambience between dry and humid N₂ at 25 °C. Pulsed measurement effectively alleviates the ID drift of the device. When the device is exposed to humidity, the |ID| is appreciably decreased in the p-channel FET-type sensor, since H₂O molecules act as an electron donor. The sensitivity of the sensor increases with increasing relative humidity up to about 68% and decreases with further increasing relative humidity.