A display substrate having a low resistance signal line and a method of manufacturing the display substrate are provided. The display substrate includes an insulation substrate, a gate line, a data line and a pixel electrode. The gate line gate line is formed through a sub-trench and an opening portion. The sub-trench is formed in the insulation substrate and the opening portion is formed through a planarization layer on the insulation substrate at a position corresponding to the position of the sub-trench. The data line crosses the gate line. The pixel electrode is electrically connected to the gate line and the data line through a switching element. Thus, a signal line is formed through a trench formed by using a planarization layer and an insulation substrate, so that a resistance of the signal line may be reduced.