An atomizer comprises an outer tube, a liquid storing member received in the outer tube, and an atomizing head located at the lower portion of the liquid storing member. A liquid storing cavity is formed in the liquid storing member. An air outlet channel is formed between the outer tube inner wall and the liquid storing member outer wall. An atomizing cavity communicating with the liquid storing cavity and the air outlet channel is formed in the atomizing head. When the liquid tobacco absorbed by the atomizing head is insufficiently atomized, the liquid storing member above the atomizer head acts as a stopper, small smoke droplets can only be released from both sides of the atomizing head, preventing user inhalation of non-atomized liquid. An electronic cigarette having the atomizer is also provided.
