The invention provides a ship body protection device for a ship, and relates to the technical field of ship body protection, the ship body protection device comprises a ship bottom, an anti-collision column is fixed on the surface of the bottommost part of the ship bottom, an anti-collision
assembly is arranged in the anti-collision column, the anti-collision
assembly comprises a storage frame, and a rolling shaft is rotatably mounted in the storage frame through a bearing and a
torsion spring; a plurality of air bags are wound on the winding shaft, every two adjacent air bags are fixedly connected, the air bag at the bottommost part of the storage frame is fixed to the interior of the anti-collision column, and a driving
assembly is arranged at the top of the ship bottom slope. The anti-collision assembly can achieve the anti-collision effect on the two sides of the ship, the anti-collision assembly can be opened when used and closed when not used, normal traveling and the size of the ship cannot be affected, the anti-collision assembly can clean the slope of the ship when unfolded, and manual cleaning of
algae and shells is replaced.