The disclosure discloses an atomizing device for an electronic cigarette and an electronic cigarette having the same. The atomizing device includes: an atomizing sleeve defining an e-liquid hole； an atomizing core removably arranged in the atomizing sleeve； and a sealing mechanism including a return spring and a liquid stopper, the liquid stopper connected to the atomizing sleeve via the return spring and configured to seal the e-liquid hole. When the atomizing core is received in the atomizing sleeve, the liquid stopper overcomes an elastic force of the return spring to open the e-liquid hole； and when the atomizing core is removed from the atomizing sleeve, the liquid stopper seals the e-liquid hole under the elastic force of the return spring.
