An electronic cigarette includes an outer housing. An atomizing sheath is received in the outer housing. An aerosol output passageway is defined between the outer housing and the atomizing sheath. An extending portion extends inwards from an inner wall of the atomizing sheath to divide the atomizing sheath into a first sleeve body and a second sleeve body for respectively storing atomizing liquid therein. The extending portion blocks incompletely the first sleeve body from the second sleeve body so that the first sleeve body and the second sleeve body are spatially communicated with each other. An atomizing core is disposed in the second sleeve body. An atomizing passageway is formed in the atomizing core. The extending portion forms therein an airflow path penetrating a wall of the atomizing sheath. The airflow path is used to spatially communicate the atomizing passageway with the aerosol output passageway.