A spray assembly including a spray pipe with a bottom provided with a plurality of first through holes, each having a nozzle, wherein the nozzle includes a slider with an area larger than the first through hole, to cover the first through hole. The nozzle is connected to the slider and protrudes from the first through hole; the nozzle also includes a locking member to connect the slider to the spray pipe. The slider can move to adjust the position of the nozzle in the first through hole. There also provides a wet etching device including a spray unit, wherein the spray unit includes a plurality of spray assemblies as mentioned above, and a plurality of spray pipes in the plurality of spray assemblies are arranged in parallel with each other or approximately in parallel with each other.