To provide a releasable composition which excels in photocurability and can be cured by irradiation with active energy rays such as light, electron rays, and x-rays in a short period of time, and further is advantageous in the total cost aspect due to its easy preparation, and furthermore can give a cured film usable in a release paper, a release film and the like.

The radiation-curable silicone-containing releasable composition comprises (A) a liquid cationically polymerizable silicone compound, (B) a photocationic polymerization initiator having an onium salt structure, and (C) a sensitizer having a solubility at 25°C of ≥0.1 pt.wt. based on 100 pts.wt. silicone compound of component (A).