An electronic cigarette, comprising: a mouthpiece assembly, the mouthpiece assembly comprising a mouthpiece, a first seal ring adapted to seal the mouthpiece, a decorative ring, a first fixed seat adapted to fix the mouthpiece, a second seal ring adapted to seal the first fixed seat, a decorative cover, a fixed cover, a fixed ring adapted to fix the fixed cover, and a slide block; an atomizing assembly, the atomizing assembly comprising a silicone seal, a pin, a spring, a second fixed seat adapted to fix the slide block, a vapor regulating ring, a second seal ring adapted to seal the vapor regulating ring, a glass tube, a third seal ring adapted to seal an upper part of the glass tube, a fourth seal ring, and an atomizing unit; and a base assembly, the base assembly comprising a fifth seal ring adapted to seal a lower part of the glass tube, a base, an insulation ring, and a joint; wherein: the first seal ring and the decorative ring 3 are sheathed on the mouthpiece; the mouthpiece is fixed on the first fixed seat; the first fixed seat comprises a side wall comprising an annular groove, and the second seal ring is embedded in the annular groove; the first fixed seat is screwed on the decorative cover; the fixed ring is sheathed on the fixed cover; the decorative cover is disposed on the fixed cover; the slide block is disposed in the fixed cover; the silicone seal is disposed on the second fixed seat; the second fixed seat comprises an upper annular groove and a lower annular groove, and the second seal ring and the third seal ring are disposed in the upper annular groove and the lower annular groove, respectively; the vapor regulating ring is connected to the second fixed seat; the fourth seal ring is embedded in the second fixed seat; the atomizing unit is inserted in the second fixed seat; the glass tube is in threaded connection to the second fixed seat; the spring is sheathed on the pin; the second fixed seat comprises a location hole, and the pin is inserted in the location hole; the second fixed seat comprises a side wall comprising a plurality of air inlets, and the atomizing unit comprises a side wall comprising a plurality of holes; the plurality of air inlets communicates with the plurality of holes; and the fifth seal ring is sheathed on the base and embedded in the glass tube; the insulation ring is sheathed on the joint; the joint is inserted in a central hole of the base; and the base is in threaded connection to the atomizing unit. a mouthpiece assembly, the mouthpiece assembly comprising a mouthpiece, a first seal ring adapted to seal the mouthpiece, a decorative ring, a first fixed seat adapted to fix the mouthpiece, a second seal ring adapted to seal the first fixed seat, a decorative cover, a fixed cover, a fixed ring adapted to fix the fixed cover, and a slide block; an atomizing assembly, the atomizing assembly comprising a silicone seal, a pin, a spring, a second fixed seat adapted to fix the slide block, a vapor regulating ring, a second seal ring adapted to seal the vapor regulating ring, a glass tube, a third seal ring adapted to seal an upper part of the glass tube, a fourth seal ring, and an atomizing unit; and a base assembly, the base assembly comprising a fifth seal ring adapted to seal a lower part of the glass tube, a base, an insulation ring, and a joint; the first seal ring and the decorative ring 3 are sheathed on the mouthpiece; the mouthpiece is fixed on the first fixed seat; the first fixed seat comprises a side wall comprising an annular groove, and the second seal ring is embedded in the annular groove; the first fixed seat is screwed on the decorative cover; the fixed ring is sheathed on the fixed cover; the decorative cover is disposed on the fixed cover; the slide block is disposed in the fixed cover; the silicone seal is disposed on the second fixed seat; the second fixed seat comprises an upper annular groove and a lower annular groove, and the second seal ring and the third seal ring are disposed in the upper annular groove and the lower annular groove, respectively; the vapor regulating ring is connected to the second fixed seat; the fourth seal ring is embedded in the second fixed seat; the atomizing unit is inserted in the second fixed seat; the glass tube is in threaded connection to the second fixed seat; the spring is sheathed on the pin; the second fixed seat comprises a location hole, and the pin is inserted in the location hole; the second fixed seat comprises a side wall comprising a plurality of air inlets, and the atomizing unit comprises a side wall comprising a plurality of holes; the plurality of air inlets communicates with the plurality of holes; and the fifth seal ring is sheathed on the base and embedded in the glass tube; the insulation ring is sheathed on the joint; the joint is inserted in a central hole of the base; and the base is in threaded connection to the atomizing unit.