The invention concerns a rotary type bag manufacturing machine which feeds continuously material paper (R) to form angulated bottom bags (B) with handles (T) in which a top edge (S2) with the handles (T) pasted can be folded toward an inside in the manufacturing process. Material paper (R) wound in a roll is continuously fed out. After forming lateral slits (15) and Letter-J-shaped nicks (16) on the material paper (R) by an incising device (4), reinforcing papers (T1) for handles (T) formed by a handle forming device 2 are pasted. Then, a cutting device (6) cuts off the material paper (R) on a cut line aligned with the lateral slits (15) to thereby form the material paper (R) with the handles (T) which remains unfolded in a plane. A cut end portion (S2) with each handle (T) pasted is folded toward an inside to invisibly cover each reinforcing paper (T1) for the handle (T). Thereafter, angulated bottom paper bags (B) are formed through a paper tube forming process and a bottom folding process.