The invention discloses a secondary plug-in structure of a drawer unit in a drawer cabinet. The secondary plug-in structure comprises a static contact installation plate, a static contact body fixed on the static contact installation plate, a movable contact base, a movable contact body fixed on the movable contact base and a guiding device installed between the static contact installation plate and the movable contact base. The guiding device comprises a guiding pin and a guiding column, which are aligned to each other. An inserting hole matching the guiding pin is arranged in the guiding post. The plug-in end of the guiding pin is of a gradually-contracting structure and/or the plug-in end of the guiding column is of a gradually-opened structure. Compared with the prior art, by use of the guiding device comprising the guiding pin and the guiding column, which cooperate with each other, via the gradually-opened and/or the gradually-contracting plug-in head structure, few possible errors during plug-in of the movable contact body and the static contact body can be effectively eliminated, thereby reducing difficulty level in manufacturing of the drawer unit and extending service life of the drawer unit.