Abstract: A basal portion for locking and fixing of hanging yarn (7) to bag main body (3) is determined in accordance with the amount of extraction subject mass (T) placed in the bag main body so that within the plane of top face triangle (12) as a constituent of the bag main body (3) of inverted triangular pyramid form with its vertex downward, the vertex comes on a line connecting the basal portion and gravity center (d) or in the vicinity thereof when the bag main body (3) is hung. When the bag main body (3) is pulled up by pinching tag (5), the hot water as extractant within the bag main body (3) rapidly falls by virtue of the weights of the extraction subject mass (T) and hot water therearound to thereby attain complete pouring within a relatively short period of time.