The invention relates to a following floating clamping device and a following floating method. A left guide wheel and a right guide wheel of a clamping element are connected with a lower supporting body through a guide wheel shaft. An upper supporting body is connected with the lower supporting body through a pin shaft. A spring shaft is connected with the bottom of a return sleeve through a bolt. The spring shaft is sleeved with a spring. A spring base covers the spring, a groove in the bottom of the spring base and the end of the spring shaft are in pilot fit in an inserted mode, a gland covers the spring base, the gland penetrates through a gland through hole in the middle of an installation plate and is connected with the return sleeve through bolts, the gland is sleeved with a fixing sleeve, and a spring force adjusting bolt is in threaded connection with a screw thread through hole in the middle of the gland. The following floating clamping device and the following floating method have the advantages that the clamping element or clamping force moves along with moving of a workpiece in the machining process, so that a clamping position is close to a cutter all the time, and it is guaranteed that clamping force on a portion which is being machined is reliable; the clamping device can float correspondingly along with evenness or height changes of a clamped face of the workpiece, and adaptability is large; clamping force can be adjusted according to changes of the workpiece and clamping force requirements.