The invention discloses a separating type spindle box structure. The separating type spindle box structure comprises a separating type spindle head and a socket, wherein the separating type spindle head and the socket are connected through a positioning shaft. The spindle box is of the separating type structure, an original integrated spindle box is divided into two sections, the portion, close to a stand column, of the original integrated spindle box is designed to be the standard socket and therefore the effect that when a spindle is replaced, the portion, matched with the stand column, of the spindle box does not need to be dismounted is achieved, a Z-axis nut seat does not need to be recalibrated, and therefore assembly efficiency can be improved. Meanwhile, according to the separating type structure, the positioning shaft is used for positioning, the assembly efficiency is further improved, and therefore assembling time is shortened to a large extent. Besides, the separating type spindle box can be designed to be in different standards according to spindles in different shapes, the spindle box is enabled to be a standard component in an enterprise and can be directly utilized in the developing process of a novel machine, and therefore design efficiency is greatly improved, stock in a warehouse is reduced, and cost is lowered at the same time.