Ship arrest refers to the civil law procedure whereby a ship or similar marine vessel may be arrested by judicial process and held under state authority in a particular jurisdiction pending the determination of present or future claims relating to the vessel. The ship is detained by judicial process for the purpose of securing a maritime claim, or for unseaworthiness and certain other conditions.

A ship may be "arrested" and detained in port by a court order in support of a maritime lien claim by creditors against the vessel.

The grounds upon which a ship may be arrested vary under the legal systems of different countries. But common grounds which may permit arrest may include:

damage to cargo carried by the ship
damage caused by a collision with the ship
to protect a mortgage or maritime lien over the ship
unpaid pilotage or towage relating to the ship