Abstract: Introduce in detail of the HSK type interface of the tool spindle used in the turning and milling complex machining center. Analyze the form of the tool shank of the HSK type. Describe the connection between the tool shank and the taper hole, analyze the influence of the tool shank of HSK-A and HSK-T on the machining accuracy. The tool handle selection of the tool spindle and the adjustment mode on the machine tool are described in detail, provides the theoretical basis and practical operation method for effectively improving the machining accuracy of the machine tool.