A display device comprising: a display panel comprising a flexible region and a low flexibility region (PA,PB) having lower flexibility than the flexible region, each of the flexible region and the low flexibility regions comprising pixels, the flexible region comprising: a first transistor comprising a first semiconductor layer and a first gate electrode, a first conductor connected to the first semiconductor layer, and a first interlayer insulating layer between the first transistor and the first conductor; and the low flexibility region comprising: a second transistor comprising a second semiconductor layer and a second gate electrode, a second conductor connected to the second semiconductor layer, and a second interlayer insulating layer between the second transistor and the second conductor; wherein a ratio of a channel width to a channel length of the first transistor is different from a ratio of a channel width to a channel length of the second transistor; characterized in that the first and the second interlayer insulating layers are formed of respectively different materials and may have different structures from each other; the first interlayer insulating layer comprises an organic insulating material; and the second interlayer insulating layer comprises an inorganic insulating material, but not the said organic insulating material. a first transistor comprising a first semiconductor layer and a first gate electrode, a first conductor connected to the first semiconductor layer, and a first interlayer insulating layer between the first transistor and the first conductor; and the low flexibility region comprising: a second transistor comprising a second semiconductor layer and a second gate electrode, a second conductor connected to the second semiconductor layer, and a second interlayer insulating layer between the second transistor and the second conductor; wherein a ratio of a channel width to a channel length of the first transistor is different from a ratio of a channel width to a channel length of the second transistor; characterized in that the first and the second interlayer insulating layers are formed of respectively different materials and may have different structures from each other; the first interlayer insulating layer comprises an organic insulating material; and the second interlayer insulating layer comprises an inorganic insulating material, but not the said organic insulating material. a second transistor comprising a second semiconductor layer and a second gate electrode, a second conductor connected to the second semiconductor layer, and a second interlayer insulating layer between the second transistor and the second conductor; wherein a ratio of a channel width to a channel length of the first transistor is different from a ratio of a channel width to a channel length of the second transistor; characterized in that the first and the second interlayer insulating layers are formed of respectively different materials and may have different structures from each other; the first interlayer insulating layer comprises an organic insulating material; and the second interlayer insulating layer comprises an inorganic insulating material, but not the said organic insulating material.