A cylindrical sampling nozzle for piercing a sampling container with rubber to aspirate a sample in the container, the nozzle comprising: a first straight portion being a root straight portion; a second straight portion smaller in outside diameter than the first straight portion, said second straight portion being a tip-side straight portion; an intermediate tapered portion disposed between the first straight portion and the second straight portion; a hollow extending lengthwise of the sampling nozzle, the hollow including an opening for aspirating the sample; a first surface disposed at an end of a tube having the hollow, the first surface having a plane surrounding the opening; a second surface disposed opposite the first surface, said second surface being a tapered surface and a tip of the sampling nozzle formed by an intersection line of the first surface and the second surface, wherein: the tip is disposed at an end of the second straight portion; the hollow which is not bent near the tip includes the opening; characterized in that the second surface has a curved surface that: - is curved in a circumferential direction of a cylindrically-shaped portion of the sampling nozzle and - is tilted linearly in a lengthwise sectional view of the sampling nozzle; and a distance between the tip of the sampling nozzle and an end of the second surface on a root side of the second surface of the sampling nozzle is shorter than a distance between the tip of the sampling nozzle and an end of the first surface on a side of the root straight portion of the first surface of the sampling nozzle. a first straight portion being a root straight portion; a second straight portion smaller in outside diameter than the first straight portion, said second straight portion being a tip-side straight portion; an intermediate tapered portion disposed between the first straight portion and the second straight portion; a hollow extending lengthwise of the sampling nozzle, the hollow including an opening for aspirating the sample; a first surface disposed at an end of a tube having the hollow, the first surface having a plane surrounding the opening; a second surface disposed opposite the first surface, said second surface being a tapered surface and a tip of the sampling nozzle formed by an intersection line of the first surface and the second surface, the tip is disposed at an end of the second straight portion; the hollow which is not bent near the tip includes the opening; the second surface has a curved surface that: - is curved in a circumferential direction of a cylindrically-shaped portion of the sampling nozzle and - is tilted linearly in a lengthwise sectional view of the sampling nozzle; and - is curved in a circumferential direction of a cylindrically-shaped portion of the sampling nozzle and - is tilted linearly in a lengthwise sectional view of the sampling nozzle; and a distance between the tip of the sampling nozzle and an end of the second surface on a root side of the second surface of the sampling nozzle is shorter than a distance between the tip of the sampling nozzle and an end of the first surface on a side of the root straight portion of the first surface of the sampling nozzle.