The geographic position of the port places it in close proximity to major shipping routes such as the Strait of Hormuz.

The administration of the port is carried out by the Karachi Port Trust, which was established in the nineteenth century.

Karachi was again a military base and port for supplies to the Russian front during the Second World War (1939–1945).

In 1947, Karachi became the capital of the new nation of Pakistan, resulting in a growth in population as it absorbed hundreds of thousands of refugees.

The history of the port is intertwined with that of the city of Karachi.

Several ancient ports have been attributed in the area including "Krokola", "Morontobara" (Woman's Harbour) (mentioned by Nearchus), and Debal (a city captured by the Muslim general Muhammad bin Qasim in 712 CE).

The period between 18 saw a marked increase in trade, especially during the American Civil War when cotton from Sindh replaced American cotton as a raw material in the British textile industry and the opening of the Suez Canal in 1869.

Another major export was oil brought by rail from the Sui region in Balochistan.

The modern port began to take shape in 1854, when the main navigation channel was dredged and a mole or causeway was constructed to link the main harbour with the rest of the city.

This was followed by construction of Manora breakwater, Keamari Groyne, the Napier Mole Bridge and the Native Jetty Bridge.

A number of British companies opened offices and warehouses in Karachi and the population increased rapidly.

By 1852, Karachi was an established city with a population of 14,000 and a prosperous overseas trade.

There is a reference to the early existence of the port of Karachi in the "Umdah", by the Arab navigator Sulaiman al Mahri (AD 1511), who mentions "Ras al Karazi" and "Ras Karashi" while describing a route along the coast from Pasni to Ras Karashi.