A thin film transistor substrate includes a plurality of thin film transistors arranged in columns and rows respectively on a substrate. Each of the thin film transistors includes a laser annealed part in which an amorphous silicon layer that forms a channel region is laser annealed to be a polysilicon layer, each laser annealed part is disposed with a designed pitch in a scanning direction in which a laser light for laser annealing and the substrate move relatively to each other, and the laser annealed part is provided within a channel width formed in a direction orthogonal to the scanning direction and being narrower than the channel width.