A GOA circuit, a display device, and a driving method of GOA circuit are disclosed. A N-th level GOA unit is configured for charging the N-th level horizontal scanning line (G(N)) within a display area of the display device. The N-th level horizontal scanning line (G(N)) connects to GAS. In response to the GAS, the horizontal scanning lines corresponding to all of the GOA units are in a charging state. In this way, the horizontal scanning lines at each level are connected to the GAS, such that when the GAS are valid, the corresponding horizontal scanning line at each level are in the charging state of in an on-state so as to realize the All Gate On function.