Provided are a tire noise reduction device allowing rapid and reliable puncture-repair of a pneumatic tire provided with an annular sound absorbing member on the inner surface of a tread portion of the tire, and a pneumatic tire provided with the tire noise reduction device. The tire noise reduction device includes: the annular sound absorbing member made of a porous material; and a repair liquid permeable layer stacked on an outer peripheral surface of the sound absorbing member. The repair liquid permeable layer has many continuous pores and has a flow resistance lower than that of the porous material. The tire noise reduction device is mounted on the inner peripheral surface of a tread portion of the pneumatic tire.