A mixed smoking set for conventional cigarette and electronic cigarette, wherein it comprises an electronic cigarette cartridge, a mouthpiece is provided above the electronic cigarette cartridge, a cigarette holder is provided below the electronic cigarette cartridge, a cigarette smoke passage of the cigarette holder extends into the mouthpiece through the electronic cigarette cartridge; the electronic cigarette cartridge includes a cigarette cartridge body, an electric control mechanism is provided below the cigarette cartridge body, there is a cavity in the electric control mechanism, and the cigarette holder is disposed in the cavity; the cigarette cartridge body includes a cigarette cartridge shell; an electronic-cigarette-oil storage chamber is provided in the cigarette cartridge shell, an electronic cigarette heating atomizer is provided in the electronic-cigarette-oil storage chamber, the electronic cigarette heating atomizer is connected to the electric control mechanism, the electronic cigarette heating atomizer is connected to an electronic-cigarette smoke passage provided on the electronic-cigarette-oil storage chamber, the electronic-cigarette smoke passage is connected to the mouthpiece; characterized in that the electronic-cigarette smoke passage is independent of the cigarette smoke passage; the mouthpiece includes a mouthpiece shell, a smoke mixing chamber is provided in the mouthpiece shell, the cigarette smoke passage and the electronic-cigarette smoke passage are all connected to the smoke mixing chamber, a mouthpiece body with a through hole therein is provided on the mouthpiece shell at a top of the smoke mixing chamber; a plurality of oblique plates are provided in the through hole of the mouthpiece body, interspaces formed by the through hole and each of the plates are arranged in a staggered layout; the cigarette holder is snapped into the electronic cigarette cartridge and is detachable from the electronic cigarette cartridge, wherein the cigarette holder includes a hollow holder shell, and a smoke passage connection member is provided on a top of the holder shell; when the cigarette holder is detached from the electronic cigarette cartridge, the smoke passage connection member is able to be used as a mouthpiece for smoking a conventional cigarette. the electronic cigarette cartridge includes a cigarette cartridge body, an electric control mechanism is provided below the cigarette cartridge body, there is a cavity in the electric control mechanism, and the cigarette holder is disposed in the cavity; the cigarette cartridge body includes a cigarette cartridge shell; an electronic-cigarette-oil storage chamber is provided in the cigarette cartridge shell, an electronic cigarette heating atomizer is provided in the electronic-cigarette-oil storage chamber, the electronic cigarette heating atomizer is connected to the electric control mechanism, the electronic cigarette heating atomizer is connected to an electronic-cigarette smoke passage provided on the electronic-cigarette-oil storage chamber, the electronic-cigarette smoke passage is connected to the mouthpiece; characterized in that the electronic-cigarette smoke passage is independent of the cigarette smoke passage; the mouthpiece includes a mouthpiece shell, a smoke mixing chamber is provided in the mouthpiece shell, the cigarette smoke passage and the electronic-cigarette smoke passage are all connected to the smoke mixing chamber, a mouthpiece body with a through hole therein is provided on the mouthpiece shell at a top of the smoke mixing chamber; a plurality of oblique plates are provided in the through hole of the mouthpiece body, interspaces formed by the through hole and each of the plates are arranged in a staggered layout; the cigarette holder is snapped into the electronic cigarette cartridge and is detachable from the electronic cigarette cartridge, wherein the cigarette holder includes a hollow holder shell, and a smoke passage connection member is provided on a top of the holder shell; when the cigarette holder is detached from the electronic cigarette cartridge, the smoke passage connection member is able to be used as a mouthpiece for smoking a conventional cigarette.