PURPOSE: To obtain the title spinneret of preventing formation of waterdrops which condense during temperature of the spinneret being lower than a dew point in an atmosphere of the spinneret, are stuck to spun hollow yarn membrane and cause uneven thickness by covering the bottom of the spinneret for spinning hollow yarn with a heat insulating substance.

CONSTITUTION: A heat insulating substance 3 such as foamed polystyrene is fixed with an epoxy resin to a spinning bottom 2 of a spinneret 1 for spinning hollow yarn made of stainless steel except a delivery hole and a place in the circumference thereof, the delivery hole and the place in the circumference thereof not covered with the heat insulating substance 3 are a circular part having 1.1-5 times as long a diameters the larger one of the outer diameter of spun hollow yarn membrane and the dimension C of the spinneret, the smaller the circle is, the better it is, the circle is such a size as not to bring the hollow yarn membrane into contact with the heat insulating substance 3 and thickness (h) of the heat insulating substance is made 0.5-30mm to spun the hollow yarn membrane while preventing formation of waterdrops which stick to the hollow yarn membrane during spinning and cause uneven thickness.