The present invention provides a TFT backplate structure and a manufacture method thereof. The TFT backplate structure comprises a switch TFT (T1) and a drive TFT (T2). The switch TFT (T1) is constructed by a first source/a first drain (61), a first gate (21), and a first etching stopper layer (51), a first oxide semiconductor layer (41), a first gate isolation layer (31) sandwiched in between. The drive TFT (T2) is constructed by a second source/a second drain (62), a second gate (22), and a second oxide semiconductor layer (42), a first etching stopper layer (51), a second gate isolation layer (32) sandwiched in between. The electrical properties of the switch TFT (T1) and the drive TFT (T2) are different. The switch TFT has smaller subthreshold swing to achieve fast charge and discharge, and the drive TFT has relatively larger subthreshold swing for controlling the current and the grey scale more precisely.