The utility model discloses a wet process spinning technique preparation filament yarn non -woven fabric's lapping device, including the frame, in the frame, follow the direction of delivery of the even fibre silk bundle of slice is provided with the conveying roller that at least a set of pivoted in opposite directions is used for carrying the even fibre silk bundle of slice, the conveying rollerpasses through the gear motor drive, the below of conveying roller is equipped with and lasts the lace curtaining that moves along the direction of delivery of the even fibre silk bundle of slice, itis used for being about to the fibre web forming mechanism that the even fibre silk bundle of slice to the lace curtaining on alternately piles up along the width orientation of lace curtaining to beprovided with one at the output of conveying roller, be provided with between conveying roller and the fibre web forming mechanism and go on constructing with the slope volume compensator of fibre web forming mechanism opposite direction transverse reciprocation tractive to the even fibre silk bundle of slice that is in the tilt state when fibre web forming mechanism moves. The utility model discloses can form wet fibre silk bundle on the lace curtaining even slice fibre web, realize the wet -laying, effectively improve the filament yarn non -woven fabric quality.