A grid modulation positively-mounted structure GaN base light emitting diode structure comprises: a sapphire substrate, an n-type GaN layer, a multi-quantum well active layer, a p-type GaN layer, a P electrode, an N electrode, a grid insulating layer and a gate electrode, wherein the n-type GaN layer is manufactured on the sapphire substrate, a bottom bed is formed at one side above the n-type GaN layer, the depth of the bottom bed is less than the thickness of the n-type GaN layer; the multi-quantum well active layer is manufactured at the other side above the n-type GaN layer where no bottom bed is arranged; the p-type GaN layer is manufactured on the multi-quantum well active layer; the P electrode is manufactured at one side of the p-type GaN layer far away from the bottom bed; the N electrode is manufactured on the bottom bed above the n-type GaN layer; the grid insulating layer is manufactured at the other side of the p-type GaN layer where no p electrode is arranged; and the gate electrode is manufactured on the grid insulating layer.