A manufacturing method of a TFT substrate uses a top gate structure and the entire process can be completely done with seven masks. The number of masks used is reduced. The manufacturing process of a TFT substrate is simplified. Product yield can be increased to effectively improve productivity. Heavy and light ion doping can be simultaneously achieved with one single doping operation so that manufacturing cost can be reduced. By subjecting two ends of a semiconductor pattern to heavy ion doping to form a source electrode and a drain electrode, the manufacturing steps can be reduced and the source electrode and the drain electrode so formed do not need to extend through a via hole formed in an interlayer dielectric layer to contact the two ends of the active layer thereby effectively reducing contact resistance and improving product yield. Also provided is a TFT substrate manufactured with the method.