An electronic cigarette comprising: an atomizer comprising one of a first connector and a second connector; and a power supply comprising the other of a first connector and a second connector; wherein the first connector comprises a cylindrical plug, the plug having a recessed portion in a side surface of the plug, wherein the recessed portion is formed on the external surface of the cylindrical plug; wherein the second connector comprises a holder, a movable component, and a force exerting component; wherein the holder is configured for receiving the plug, the movable component is movable arranged on a sidewall of the holder, and the force exerting component is configured for exerting an elastic force on the movable component; the movable component is configured for ejecting from the sidewall to engage in the recessed portion while the plug is inserted into the holder, and for retracting relative to the sidewall during insertion of the plug into the holder; characterized in that wherein the force exerting component comprises an elastic ring, and the sidewall of the holder defines an annular groove, the movable component comprises a plurality of steel balls, the sidewall further defines a plurality of mounting holes, the mounting holes extend through the sidewall, and communicate with the annular groove; wherein the steel balls are engaged in corresponding mounting holes, the elastic ring is engaged in the annular groove, the elastic ring is configured for exerting an elastic force on the steel balls, so that the steel balls are tightly engaged in the mounting holes, and part of each steel ball protrudes from the sidewall; or wherein the force exerting component comprises a fixed ring and a plurality of springs, the sidewall defines an annular groove and a plurality of mounting holes, the movable component has a plurality of second pins, the mounting holes extend through the sidewall, and communicate with the annular groove, the fixed ring is engaged in the annular groove, the second pins are engaged in corresponding mounting holes; wherein each spring is arranged between the fixed ring and a respective second pin, the springs are configured for exerting an elastic force on a corresponding second pin, so that the second pins are tightly engaged in the mounting holes, and ends of the second pins protrude from each mounting hole. an atomizer comprising one of a first connector and a second connector; and a power supply comprising the other of a first connector and a second connector; wherein the first connector comprises a cylindrical plug, the plug having a recessed portion in a side surface of the plug, wherein the recessed portion is formed on the external surface of the cylindrical plug; wherein the second connector comprises a holder, a movable component, and a force exerting component; wherein the holder is configured for receiving the plug, the movable component is movable arranged on a sidewall of the holder, and the force exerting component is configured for exerting an elastic force on the movable component; the movable component is configured for ejecting from the sidewall to engage in the recessed portion while the plug is inserted into the holder, and for retracting relative to the sidewall during insertion of the plug into the holder; characterized in that wherein the force exerting component comprises an elastic ring, and the sidewall of the holder defines an annular groove, the movable component comprises a plurality of steel balls, the sidewall further defines a plurality of mounting holes, the mounting holes extend through the sidewall, and communicate with the annular groove; wherein the steel balls are engaged in corresponding mounting holes, the elastic ring is engaged in the annular groove, the elastic ring is configured for exerting an elastic force on the steel balls, so that the steel balls are tightly engaged in the mounting holes, and part of each steel ball protrudes from the sidewall; or wherein the force exerting component comprises a fixed ring and a plurality of springs, the sidewall defines an annular groove and a plurality of mounting holes, the movable component has a plurality of second pins, the mounting holes extend through the sidewall, and communicate with the annular groove, the fixed ring is engaged in the annular groove, the second pins are engaged in corresponding mounting holes; wherein each spring is arranged between the fixed ring and a respective second pin, the springs are configured for exerting an elastic force on a corresponding second pin, so that the second pins are tightly engaged in the mounting holes, and ends of the second pins protrude from each mounting hole.