An aerosol generator includes a container and an atomizing module arranged in the container. The container has a liquid chamber and an aerosol chamber respectively arranged at two opposite sides of the atomizing module. The atomizing module includes an annular vibration plate, a microporous member, and a circuit board. The vibration plate has a first hole, and the microporous member is disposed on the vibration plate and covers the first hole. The circuit board is electrically coupled to an electrical contact of the vibration plate. The circuit board is arranged at one side of at least part of the vibration plate, and the circuit board and the at least part of the vibration plate have a gap there-between. A projected region defined by orthogonally projecting the circuit board onto a plane overlapping with the electrical contact partially covers the least part of the vibration plate.