The invention relates to a tool coupling for connecting a tool carrier which can be driven in a rotating manner, in particular a milling tool with a machine spindle or an adapter connected to a spindle, wherein four drivers in a crosswise formation are provided for transmitting torque between the said parts and in the clamping state engage in four recesses. To allow the tool coupling to be easily operated and to be of a simple construction, and also to counteract undesired jamming, it is proposed that the drivers respectively have on the side transmitting the torque a planar face which lies with full surface-area contact against a wall of a groove-shaped recess in the clamping state, that on the opposite side the driver has a smaller positively or frictionally engaging contact with the wall there of the groove-shaped recess and that a quick-acting clamping device is provided for the axial clamping of the tool carrier and the spindle or an adapter.