Electronic cigarette, atomizer core thereof and atomizer thereof

An atomizing core of an electronic cigarette, configured to be connected to a housing of the electronic cigarette, comprising:

• a main body portion provided with a liquid storage chamber and an air flow passage that are separated from each other therein, the main body portion being disposed in a receiving chamber of the housing;
• and
• a mouthpiece portion slidably connected to the main body portion, wherein at least a portion of the mouthpiece portion is located outside the receiving chamber;
• the mouthpiece portion is provided with a suction hole, when the mouthpiece portion is located at a first position relative to the main body portion, the suction hole is in communication with the air flow passage;
• when the mouthpiece portion slides from the first position to a second position, a liquid injection position of the main body portion is exposed;
• the mouthpiece portion is provided with a stopper, when the mouthpiece portion is located at the first position relative to the main body portion and the main body portion is located in the receiving chamber, at least a portion of the stopper is located in the receiving chamber and the stopper abuts against the housing.