The present invention provides an electronic cigarette, including a cartridge, an atomizer device, and a cartridge fixing element to detachably connect the cartridge to the atomizer device. A cartridge body can be switched to be in a pre-mounting position and a mounting position to engage the cartridge fixing element. When in the pre-mounting position, a sealing element and a puncturing element of the cartridge are spaced by a certain distance or abut against each other, to ensure that a first sealing portion will not be punctured and E-liquid in the cartridge will not be contaminated before smoking. When in the mounting position, the installation of the cartridge is completed, a second sealing portion is punctured to communicate a liquid reservoir chamber with a liquid reservoir room, to allow the E-liquid in the liquid reservoir chamber to flow to the liquid reservoir room, and users can smoke.