A thin film transistor substrate includes: first and second driving chips; a plurality of signal lines respectively connected to the first and second driving chips; a plurality of first and second branch repair lines extended across the plurality of signal lines connected to the first driving chip; a plurality of third and fourth branch repair lines extended across the plurality of signal lines connected to the second driving chip; an insulating layer between the plurality of first and second branch repair lines and the plurality of signal lines connected to the first driving chip, and between the plurality of third and fourth branch repair lines and the plurality of signal lines connected to the second driving chip; a first repair line connecting the first and second branch repair lines to each other; and a second repair line connecting the third and fourth branch repair lines to each other.