Provided are a marine hose and an airbag device for a marine hose. An airbag device includes a water pressure sensor, a folded bag float attached to the outer surface of the marine hose, and an inflation device for introducing air into the bag float. The water pressure sensor activates the inflation device to inflate the folded bag float when the water pressure sensor detects that a preset water pressure value has been reached and the buoyancy provided by the inflated bag float prevents further sinking of the marine hose.