A spray nozzle includes a transmission component and a fan blade assembly. The fan blade assembly is connected to the transmission component, and can rotate with respect to the transmission component to create a vacuum inside the fan blade assembly, so that the liquid to be atomized under atmospheric pressure can enter the fan blade assembly through the transmission component. The fan blade assembly can also drive the liquid in the fan blade assembly to rotate so as to atomize the liquid and eject it from the fan blade assembly. The liquid in the fan blade assembly rotates with the fan blade assembly. A sprayer includes a body and the spray nozzle.