A thin-film transistor includes an active layer, a gate electrode, a source electrode and a drain electrode. The gate electrode overlaps the active layer. The source electrode and the drain electrode are connected to the active layer. The active layer includes a source region connected to the source electrode, a drain region connected to the drain electrode, a channel region overlapping with the gate electrode, a first resistive region between the source region and the channel region, and a second resistive region between the drain region and the channel region. The length of the first resistive region is larger than the length of the second resistive region.