To provide an inexpensive extrusion apparatus enabling the addition extrusion of unvulcanized rubber exceeding the number of exatruder main bodies and an extrusion method of an unvulcanized rubber multiple layer excellent in the low rolling resistance and grounding property of a tire using this apparatus.

An unvulcanized rubber extrusion apparatus 1 has a cylinder space wherein clamp wedges 8a, 8b extend in a revolving direction from the vicinal position of the clamp of a die holder and an unvulcanized rubber flow channel opened to the outside on the side of the die holder 7 and the cylinder space of the clamp wedges 8a, 8b and the unvulcanized rubber flow channel of the leading end part thereof, the extrusion screw 23 housed in the cylinder space and a drive means 24 rotating the extrusion screw 23 are provided as separate extrusion devices.