Probe tip portion of the biopsy needle (34) is tube axis (X1) and the first bevel consisting plane extending in a direction intersecting the tubular portion (31) and (36), the first beveled surface (36) A second oblique angle surface (37) having an angle with respect to the first oblique angle surface (36) and being a plane adjacent to the inner circumferential surface (33) of the tubular portion (31) (36) at an angle with respect to the first oblique angle surface (36) on the opposite side of the second oblique angle surface (37) with the first oblique angle surface (35) interposed therebetween and the tubular portion A third oblique surface 38 formed of a plane adjacent to the inner circumferential surface 33 of the first oblique angle surface 31 and a second oblique angle surface 37 which is a boundary between the first oblique angle surface 36 and the second oblique angular surface 37, A first boundary line (40) and a second boundary line (43) which is a boundary between the first inclined angle plane (36) and the third oblique angle plane (38) The line (43) Part (31) is a straight non-parallel to the spacing widens gradually in accordance with the go second end in the tube axis (X1) direction from (31b) in a direction toward the first end (31a).生検針の針先部(34)は、管状部(31)の管軸(X1)と交差する方向に広がる平面からなる第一斜角面(36)と、第一斜角面(36)に対して角度を有して第一斜角面(36)に隣接するとともに管状部(31)の内周面(33)に隣接する平面からなる第二斜角面(37)と、開口部(35)を間に挟んで第二斜角面(37)の反対側において第一斜角面(36)に対して角度を有して第一斜角面(36)に隣接するとともに管状部(31)の内周面(33)に隣接する平面からなる第三斜角面(38)と、第一斜角面(36)と第二斜角面(37)との境界となる第一境界線(40)と、第一斜角面(36)と第三斜角面(38)との境界となる第二境界線(43)とを含み、第一境界線(40)及び第二境界線(43)は、管状部(31)の管軸(X1)方向において第二端部(31b)から第一端部(31a)へ向かう方向へ行くに従ってその間隔が漸次広がる非平行の直線である。
