A pneumatic spinning device comprising: a nozzle block, to which a fiber is introduced; and a hollow guide shaft body unit including a fiber introducing port, to which the fiber introduced to the nozzle block is introduced and a passage adapted to guide the fiber introduced to the fiber introducing port to outside, whereby the nozzle block includes a first block portion defining a first space, to which the fiber is introduced, and a plurality of first nozzles, through which air injected to generate whirling airflow is passed, a second block portion defining a second space, through which the air from the first space is passed, and a third block portion defining a third space, through which the air from the second space is passed, the first space, the second space, and the third space are aligned from a first side toward a second side in a predetermined direction, the second space is spread at a second inner surface tapered angle from the first side toward the second side, the third space is spread at a third inner surface tapered angle greater than the second inner surface tapered angle from the first side toward the second side, the hollow guide shaft body unit includes a first shaft body portion disposed within the second space and the third space, and a second shaft body portion disposed within the third space and a region on the second side with respect to the third space, the first shaft body portion and the second shaft body portion are aligned from the first side toward the second side, the first shaft body portion is spread at a first outer surface tapered angle from the first side toward the second side, and the second shaft body portion is spread at a second outer surface tapered angle greater than the first outer surface tapered angle from the first side toward the second side, characterized in that the hollow guide shaft body unit includes a plurality of second nozzles, through which air injected to the passage is passed and in that the first space is a circular truncated cone shaped space that spreads from the upstream toward the downstream at a first inner surface tapered angle, or a continuous circular cylinder shaped space. a nozzle block, to which a fiber is introduced; and a hollow guide shaft body unit including a fiber introducing port, to which the fiber introduced to the nozzle block is introduced and a passage adapted to guide the fiber introduced to the fiber introducing port to outside, whereby the nozzle block includes a first block portion defining a first space, to which the fiber is introduced, and a plurality of first nozzles, through which air injected to generate whirling airflow is passed, a second block portion defining a second space, through which the air from the first space is passed, and a third block portion defining a third space, through which the air from the second space is passed, a first block portion defining a first space, to which the fiber is introduced, and a plurality of first nozzles, through which air injected to generate whirling airflow is passed, a second block portion defining a second space, through which the air from the first space is passed, and a third block portion defining a third space, through which the air from the second space is passed, the first space, the second space, and the third space are aligned from a first side toward a second side in a predetermined direction, the second space is spread at a second inner surface tapered angle from the first side toward the second side, the third space is spread at a third inner surface tapered angle greater than the second inner surface tapered angle from the first side toward the second side, the hollow guide shaft body unit includes a first shaft body portion disposed within the second space and the third space, and a second shaft body portion disposed within the third space and a region on the second side with respect to the third space, a first shaft body portion disposed within the second space and the third space, and a second shaft body portion disposed within the third space and a region on the second side with respect to the third space, the first shaft body portion and the second shaft body portion are aligned from the first side toward the second side, the first shaft body portion is spread at a first outer surface tapered angle from the first side toward the second side, and the second shaft body portion is spread at a second outer surface tapered angle greater than the first outer surface tapered angle from the first side toward the second side, characterized in that the hollow guide shaft body unit includes a plurality of second nozzles, through which air injected to the passage is passed and in that the first space is a circular truncated cone shaped space that spreads from the upstream toward the downstream at a first inner surface tapered angle, or a continuous circular cylinder shaped space.