To solve a problem in a conventional art related to prevention of sliding down of a pillow placed on a bed whose upper body part is raised, wherein various stoppers have been used causing complicated or fixed slipping-down preventive function, and hindering multifunctionality of the pillow.

A pneumatic pillow used for a bed capable of raising the upper body part is provided with a sheet-like slipping-down preventive part on a side corresponding to the largest side of the pillow. Self weight and friction of a pneumatic pillow body and the sheet-like slipping-down preventive part are made balanced, by which the pneumatic pillow is prevented from sliding down from the raised surface of the bed. Other stoppers are not needed, and multifunctionality is also imparted to the pneumatic pillow having reduced weight.