To accurately grasp a generation situation of a warning generated in an operation machine, the operation machine is provided with: warning generation means 55 adapted to determine whether or not there is abnormality, and in the case where there is abnormality, generate a warning； warning storage means 56 adapted to store warning information on the warning； display means adapted to display the warning information stored in the warning storage means 56； and warning erasing means adapted to erase the warning information, wherein the warning storage means 56 is configured to store warning information on a warning generated after the erasure by the warning erasing means 57.
