The invention relates to a quick multiplication method of broccoli isolated cells. The method includes the following steps: (1) preparing an MS basic culture medium; (2), obtaining and vaccinating broccoli isolated cells, namely, obtaining sterile seeds after flushing and sterilizing broccoli seeds of a current year, vaccinating the sterile seeds on the MS basic culture medium, obtaining sterile seedlings after 14 days of culturing, cutting germ and vaccinating the germ on an MS induced culture medium in a front-upward manner, and performing dedifferentiation culturing for 30 days under the conditions of darkness and temperature of 24 DEG C - 26 DEG C to obtain broccoli isolated cells; (3), multiplying the broccoli isolated cells, namely, vaccinating the broccoli isolated cells on an MS multiplication culture medium, and culturing for 15-20 days under the conditions of darkness and temperature of 24 DEG C - 26 DEG C. The quick multiplication method is simple, convenient and quick, quick multiplication and development of isolated cells can be controlled directionally, and multiplication rate of cells can be increased, so that breaking away from natural growing laws of broccoli can be realized, and multiplication cycle is shortened.