The present invention provides a method for manufacturing a TFT substrate and a structure thereof. The method for manufacturing the TFT substrate uses a connection semiconductor (42) that is formed in a semiconductor layer and is subjected to N-type heavy doping to connect a first semiconductor (41) and a second semiconductor (43) so as to connect the first TFT and the second TFT in series. The N-type heavily doped connection semiconductor (42) substitutes a connection electrode that is formed in a second metal layer in prior art techniques for preventing the design rules of the connection electrode and the second metal layer from being narrowed due to the connection electrode being collectively present on the second metal layer with signal lines of a data line and a voltage supply line and for facilitating increase of an aperture ratio and definition of a display panel. The present invention also provides a TFT substrate structure, which has a simple structure and possesses a high aperture ratio and high definition.