To improve efficiency of marine waste incineration by a fluidized furnace.

A fluidized bed 2 is formed in the lower position of a fluidized furnace 1, in which heated primary air 21 is supplied through an air-diffuser tube 18, a fuel oil 23 is blown by an in-sand burner 24 to incinerate the marine waste. Shut-off dumpers 44a and 44b, and 44 are provided respectively to a discharge duct 8 of waste-carrying equipment 9 for supplying the marine waste into the furnace and a discharge duct 14 of waste-retaining equipment 15 for retaining the marine waste to be carried to the equipment 9. Further there are provided a thermometer 47 for detecting temperature of the fluidized bed 2 and a controller 48 for sending a shut-off command to the shut-off damper 44a, 44b, and 44, at the time when the operation of the furnace 1 is judged to be suspended based on the detected value of the thermometer 47.