Abstract: Thread-cutting device for an eyelet buttonhole sewing machine, having a looper support (70) which can rotate about a vertical axis (22) and is fitted with mutually independently operable thread-cutting tools (42, 53) for a looper thread (60) and a needle thread. Provided on the looper support (70) are drive devices in the form of pneumatic cylinders (29, 30) for the thread-cutting tools (42, 53), which drive devices can be fed compressed air from a stationary compressed air source via a device (69) in the form of elastic hoses (33, 37) or of a rotary bushing. The thread-cutting device according to the invention permits the thread-cutting tools (42, 53) to be operated irrespective of the rotary position of the looper support (70).