Carcass ply forming apparatus and method for manufacturing pneumatic tyre using the same

[Purpose] The accuracy of forming a carcass ply on a core body is improved and production rate is increased through automation. [Technical scheme] A layer guide device is provided for guiding a ply piece for forming a carcass layer to a ply attaching position, and intermittently feeding the ply piece; and an attaching apparatus is used for, while feeding the ply piece at each time, forming a rectangular portion on a ply feed portion for the ply piece and attaching the rectangular portion to the external surface of the core body; moreover, the attaching apparatus comprises: a holding device including a holding unit for holding the ply feed portion on the two end portions of the ply feed portion; a slot forming device including a cutter for forming a slot in the ply piece on a rear side in a feed direction in the vicinity of the holding portion and the ply feed portion, thereby forming the rectangular portion divided by the slot on the ply feed portion; and an attaching device including a press roll which rotat