The present invention provides a TFT substrate structure, comprising a Switching TFT and a Driving TFT, and the Switching TFT comprises a first active layer, and the Driving TFT comprises a second active layer, and the first active layer and the second active layer are made by the same or different materials and the electrical properties of the Switching TFT and the Driving TFT are different. According to the different functions of the different TFTs, the present invention employs different working structures for the Switching TFT and the Driving TFT to respectively implement deposition and photolithography, and employs different materials for the active layers of the Switching TFT and the Driving TFT to differentiate the electrical properties of different TFTs in the TFT substrate. Accordingly, the accurate control to the OLED with lowest cost can be realized.