The Mercantile Marine Department is a Subordinate Office of the Directorate General, Ports and Shipping, Ministry of Maritime Affairs. The department was established in 1930 and is an integral part of Maritime Safety Administration of Pakistan. It is headed by Principal Officer who is also Registrar of Ships and Superintendent of Light Houses.

The Mercantile Marine Department was established on 1st May, 1930 and was placed under the charge of Principal Officer vide Notification No. 3-2.1/30 dated 19th April, 1930. The Principal Officer was also appointed ex-officio Shipping Master. A notice was issued stating that all notices to Mariners, Navigational warnings, duties in connection with enquires into shipping causalities, Pilgrim Ships, Light Houses, External Emigration, Examination for Competency Certificates, Registration of Ships, engagement and disengagement of seamen- all Shipping Office duties and general administration of Central and Provincial Acts pertaining to merchant shipping, Light Houses and emigration shall be carried out by this department.

The important objectives of the department are to ensure the safety of life and property at sea and inland waters, safety of navigation and protection of Marine Environment through implementation of Merchant Shipping Ordinance, National Rules and International Maritime Conventions.