An electronic cigarette having dual air passages, comprising a vaporizer and a battery rod, wherein the vaporizer is provided with a plug-in portion, the battery rod is provided with a receiving portion, the vaporizer and the battery rod are connected by insertion of the plug-in portion into the receiving portion, and a suction sensor is provided inside the battery rod, an upper portion of the battery rod is provided with a first suction sensing air passage to communicate with the suction sensor; the vaporizer comprises a mouth piece, a cigarette liquid cup, and a vaporizing device, wherein the mouth piece is sleeved on an outer wall of an upper portion of the cigarette liquid cup, and the vaporizing device is arranged inside a lower portion of the cigarette liquid cup, a vapor outlet tube is centrally provided inside the cigarette liquid cup and in communication with a mouth piece opening formed on an upper end of the mouth piece, the vaporizing device comprises a liquid isolation component, a vaporizing tube, a heating assembly, a throttle plate, a vaporizing base, and a bottom cap, the vaporizing base is provided at a bottom end of the cigarette liquid cup and a joint between the vaporizing base and the cigarette liquid cup is provided with the throttle plate, an inner space of the cigarette liquid cup above the throttle plate forms a liquid storage chamber for storing cigarette liquid; the heating assembly is arranged above the vaporizing base, and the vaporizing tube is provided above the heating assembly and connects with a lower end of the vapor outlet tube, the liquid isolation component is provided at a joint between the vaporizing tube and the vapor outlet tube to seal and isolate a liquid in the cigarette liquid cup, the bottom cup is provided at a bottom end of the vaporizing base; characterized in that, a second air inlet passage extending through the vaporizing base in a vertical direction is centrally provided in the vaporizing base, a second air inlet cavity which is in communication with the second air inlet passage is formed between the vaporizing base and the bottom cap, a lower portion of the cigarette liquid cup is formed as the plug-in portion, an air inlet gap between the inner wall of the plug-in portion and the receiving portion is formed where the plug-in portion and the receiving portion are connected, a first air inlet cavity is a gap formed between a bottom end of the bottom cap and a top end of the receiving portion, the wall of the receiving portion is provided with an air intake hole communicating with the air inlet gap and the first air inlet cavity in sequence, the bottom portion of the bottom cap is provided with a first air inlet passage for communicating the first air inlet cavity with the second air inlet cavity, and the bottom portion of the bottom cap is further provided with a second suction sensing air passage for communicating the second air inlet cavity with the first suction sensing air passage. the vaporizer comprises a mouth piece, a cigarette liquid cup, and a vaporizing device, wherein the mouth piece is sleeved on an outer wall of an upper portion of the cigarette liquid cup, and the vaporizing device is arranged inside a lower portion of the cigarette liquid cup, a vapor outlet tube is centrally provided inside the cigarette liquid cup and in communication with a mouth piece opening formed on an upper end of the mouth piece, the vaporizing device comprises a liquid isolation component, a vaporizing tube, a heating assembly, a throttle plate, a vaporizing base, and a bottom cap, the vaporizing base is provided at a bottom end of the cigarette liquid cup and a joint between the vaporizing base and the cigarette liquid cup is provided with the throttle plate, an inner space of the cigarette liquid cup above the throttle plate forms a liquid storage chamber for storing cigarette liquid; the heating assembly is arranged above the vaporizing base, and the vaporizing tube is provided above the heating assembly and connects with a lower end of the vapor outlet tube, the liquid isolation component is provided at a joint between the vaporizing tube and the vapor outlet tube to seal and isolate a liquid in the cigarette liquid cup, the bottom cup is provided at a bottom end of the vaporizing base; characterized in that, a second air inlet passage extending through the vaporizing base in a vertical direction is centrally provided in the vaporizing base, a second air inlet cavity which is in communication with the second air inlet passage is formed between the vaporizing base and the bottom cap, a lower portion of the cigarette liquid cup is formed as the plug-in portion, an air inlet gap between the inner wall of the plug-in portion and the receiving portion is formed where the plug-in portion and the receiving portion are connected, a first air inlet cavity is a gap formed between a bottom end of the bottom cap and a top end of the receiving portion, the wall of the receiving portion is provided with an air intake hole communicating with the air inlet gap and the first air inlet cavity in sequence, the bottom portion of the bottom cap is provided with a first air inlet passage for communicating the first air inlet cavity with the second air inlet cavity, and the bottom portion of the bottom cap is further provided with a second suction sensing air passage for communicating the second air inlet cavity with the first suction sensing air passage.