A GOA circuit based on LTPS semiconductor TFT includes a plurality of GOA units which are cascade connected, in which an Nth GOA unit includes a pull-up control part, a pull-up part, a first pull-down part and a pull-down holding part. The pull-down holding part utilizes a high/low voltage reverse design and includes first, second and third DC constant low voltage levels, which are sequentially abated, and a DC constant high voltage level so that the influence of electrical property of the LTPS semiconductor TFT to the GOA driving circuit and particularly the bad function due to the electric leakage issue can be solved. Also, the existing issue that the second node voltage level of the pull-down holding circuit part in the GOA circuit based on the LTPS semiconductor TFT cannot be at higher voltage level in the functioning period can be solved.