An exemplary atomizer includes a housing, a receiving chamber defined in the housing, an atomizing unit arranged in the housing, and a deformable valve hermetically engaged in the liquid inlet. The receiving chamber is configured for storing tobacco liquid, and the receiving chamber has a liquid inlet. The atomizing unit is configured for generating aerosol from the tobacco liquid. The valve is capable of deforming upon an external force exerted by an injector, so that tobacco liquid can be injected into the receiving chamber via the liquid inlet, and capable of restoring to its original shape to seal the liquid inlet when the injector is moved out.
