A multi-sample introduction propulsion mechanism has a structure including a first sample holder pushing mechanism, a second sample holder pushing mechanism, an optocoupler and a base; the first pushing mechanism includes a first guide rail, a first sliding block and a first shifting fork fixed plate, and the first shifting fork fixed plate is provided with a first shifting fork; a first driving device includes a first driving motor connected with a first driving wheel, and a first connection block is fixedly connected with a first transmission belt; the second pushing mechanism includes a second guide rail and a second sliding block; the front end face of the second sliding block is provided with a second shifting fork guide rail connection block, and the second shifting fork guide rail connection block is provided with a second shifting fork; a second driving device includes a second driving motor, an output shaft of the second driving motor is connected with a second driving wheel, the driving wheel is in transmission connection with a second driven wheel through a second transmission belt, and a second connection block is fixedly connected with the second transmission belt; the optocoupler is fixed on the side wall of the base and is provided with a groove for a coded disc to pass through. The propulsion mechanism has the advantages of improving the detection efficiency, reducing the detection period and improving the sample introduction speed.