James Grant (1772 – 11 November 1833) was a Scottish born British Royal Navy officer and navigator in the early nineteenth century.

His instructions were to proceed to Australia to prosecute "the discovery and survey of the unknown parts of the coast of New Holland", although it was always intended that he should hand the ship to Matthew Flinders and take command of HMS Supply.

Here Grant received dispatches from the Duke of Portland advising him of the discovery of a strait between New South Wales and Van Diemen's Land.

Lady Nelson entered the heads at Port Jackson at six in the evening of 16 December 1800 after a passage of seventy-one days from Cape Town.

When he arrived, it transpired that Flinders had returned to England and that Supply had been laid up as a hulk at Sydney, and Governor King reappointed him to the Lady Nelson.

On 10 June 1801 Grant sailed to the Hunter River conveying Lieutenant Colonel Paterson, to consider the question of a settlement there and the probable extent of the coal deposits.