To provide a field effect transistor which assures a large ON/OFF ratio in addition to a large field effect mobility, and can also be manufactured with the simplified method.

The field effect transistor comprises a semiconductor active layer 6, a gate electrode 2, a source electrode 4, and a drain electrode 5. The semiconductor active layer 6 is formed of a layer including at least one liquid crystal compound having a polymerization group, and a layer including at least a kind of compound having a photosensitive isomerization group or a layer including at least a kind of compound having both photosensitive isomerization group and liquid crystal functional group.