An electronic cigarette, with an upper-cover assembly 10 and a lower-cover assembly 20. The upper-cover assembly and the lower-cover assembly are cooperated to together form an oil-storing chamber 30. The lower-cover assembly comprises a connecting element 23, a bottom cover 21 and a sealing element 22 detachably connected to the bottom cover. One end of the connecting element is connected with the bottom cover, and the other end of the connecting element is connected with the upper-cover assembly. The bottom cover defines an oil-refilling hole (211,fig. 4). The connecting element defines a through-hole 231 communicating with both the oil-refilling hole and the oil-storing chamber. When the sealing element is connected with the bottom cover, the sealing element extends through the oil-refilling hole and is accommodated in the through hole. The e-cigarette may also have a heating assembly 42, 43 with an atomizing-chamber 50 and the upper-cover assembly may also have a casing 11 and a connecting tube 12 inside the casing. The connecting tube may connect with the heating assembly and communicate with the atomizing-chamber. There may be an atomizing-casing 41 defining the atomizing-chamber which may have an oil permeation hole which connects the atomizing-chamber to the oil-storing chamber.
