We have successfully proposed a patterned P3HT thin-film transistor with cross-linked PVP as a passivation material which was cured at low temperature. The active P3HT layer was isolated via photolithographic technique and O2 plasma RIE etching process. In this method, the leakage current could be reduced effectively compared with that of non-patterned device. Although the mobility was degraded 40 %, but the on/off ratio was significantly improved by over three orders and also the subthreshold swing was compatible with the amorphous Si-TFTs (∼1.5 V/decade). Moreover, we also employed this low temperature curing PVP (120 0C) films as the gate dielectrics which exhibited excellent insulating property with high on/off ratio 1.58×104 and good subthreshold swing 1.66 V/decade.