To provide a release film which does not need to be changed often for hot press and is easy to be changed; a releasable cushion material which can reduce the frequency of changing a cushion material main body; and a process for producing a printed board with good productivity and low cost.A release film 10 which is to be provided on a surface of a cushion material made of silicone rubber, and which has a layer 14 containing Si on one side of a substrate 12 made of a fluororesin; a releasable cushion material wherein the release film is provided on a surface of the cushion material made of silicone rubber so that the layer containing Si is located on the cushion material side; and a process for producing a printed board wherein, when a laminate of a printed board main body and coverlay films is subjected to hot press as sandwiched between press boards, the release film is disposed on a surface of the cushion material of the coverlay film side so that the layer containing Si is located on the cushion material side.