The invention relates to a device (10) for machining, in particular eroding and grinding, rotational workpieces (44) provided with cutting edges, with a machine base (12), a machining mechanism (14), which can be displaced relative to the machine base (12), and a workpiece positioning mechanism (18), which can be displaced relative to the machine base (12), wherein the machining mechanism (14) has at least one machining tool (30), which is attached in a rotatably drivable manner to a slide arrangement (20), which can be displaced in relation to the machine base (12), for machining a functional portion to be machined of the rotational workpiece (44), and wherein the workpiece positioning mechanism (18) has a workpiece holding mechanism (46), which can be displaced relative to the machine base (12) and holds a holding portion of the rotational workpiece (44) directly or via a holding adapter for attaching the rotational workpiece (44) to the workpiece positioning mechanism (18). In this device the workpiece holding mechanism (46) is oriented relative to the machine base (12) and holds the holding portion of the rotational workpiece (44) such that the rotational workpiece (44) is arranged with its functional portion suspended substantially in the vertical direction for machining.