An electronic cigarette includes: a housing a mouthpiece located at one end of the housing, the mouthpiece defining an air outlet a liquid reservoir received in the housing, the liquid reservoir defining a chamber for storing liquid and a channel communicated with the air outlet a stopper located at an end of the liquid reservoir adjacent to the mouthpiece sealing the chamber an atomizing assembly received in the housing and connected to the liquid reservoir, the atomizing assembly including a heating element configured to absorb the liquid and atomize the liquid into atomized gas and a power source connected to the atomizing assembly, the power source being configured to provide power for the heating element. When refueling the liquid, a syringe needle can penetrate the stopper and inject the liquid into the cavity. Such injection procedure can be more conveniently performed without dissembling the liquid reservoir.