The invention discloses an inner cooling cutting fluid fast-changing knife handle. The inner cooling cutting fluid fast-changing knife handle is installed on an outer cooling machine tool spindle BT60 knife bin and comprises a BT60 knife handle body, a pull rod, a rolling sleeve and a BT50 knife handle body. The BT50 knife handle body is installed into a conical hole of the BT60 knife handle body. One end of the pull rod is connected with the BT50 knife handle body. The other end of the pull rod is fixed to the BT60 knife bin through a machine tool spindle pull claw. The rolling sleeve is of a cavity structure. The periphery of the rolling sleeve is provided with a connecting-in opening. The BT60 knife handle body is sleeved with the rolling sleeve. The pull rod is provided with an annular groove. The bottom of the annular groove is provided with an inner conical hole. The front end of the pull rod is of a hollow structure. The inner conical hole communicates with the hollow structure. The hollow structure communicates with a lubrication hole of an inner cooling knife in the BT50 knife handle body. According to the inner cooling cutting fluid fast-changing knife handle, the labor intensity for changing a BT60 knife is relieved, thus non-inner-cooling cutting fluid machine tool spindle achieves cooling of inner cooling cutting fluid, scrap iron produced by machining is discharged in time, knife abrasion is reduced, the life of the knife is prolonged, the appearance quality and dimensional accuracy of a workpiece are improved, and work efficiency is improved.