To provide a photopolymerizable composition having high sensitivity, free of a variation of sensitivity even in long-term storage and suitable for a photosensitive planographic printing plate for CTP which records digital data with a laser light source.

The photopolymerizable composition comprises: A) a monomer containing an addition-polymerizable ethylenic double bond: B) a photopolymerization initiator; C) a polymeric binder; and a compound having a structure represented by the formula R1-(C=O)-X1 wherein R1 is an N-containing cyclic substituent; X1 is hydroxyl, -OR2 or -NHR2; and R2 is alkyl, aryl, a heterocyclic group or alkenyl, each of which may have a substituent.