To provide a film containing a thermosetting crosslinked cyclic olefin resin obtained by ring-opening metathesis polymerization of a cyclic olefin monomer, and having sufficient releasability to resins used in sealing materials, prepregs or adhesives and satisfactory mechanical strength such as tensile elongation at break and tensile strength at break, and a method for producing the same.

The thermosetting crosslinked cyclic olefin resin film is obtained by ring-opening metathesis polymerization of a polymerizable composition containing (a) 100 pts.mass of a cyclic olefin monomer and (b) 0.2-13 pts.mass of a petroleum resin.