Sir Thomas Brandon, of Southwark, Surrey, and of Duddington, Northamptonshire (died 27 January 1510) was an English soldier, courtier and diplomat.

A contemporary manuscript speaks of Sir Thomas as having 'greatly favoured and followed the party of Henry, earl of Richmond.’ He was appointed to the embassy charged with concluding peace with France in 1492, and again in 1500 he formed one of the suites which accompanied Henry VII to Calais to meet the Archduke Philip of Austria.

The main object of this treaty was to induce Maximilian to withdraw his support from Edmund de la Pole, 3rd Duke of Suffolk, and banish him and the other English rebels from his dominions.

In the records of a tournament held in 1494 to celebrate the creation of the Prince Henry as Knight of the Bath and Duke of York, Brandon is mentioned as having distinguished himself.

In October 1507 he was sent to meet Balthasar de Castiglione, ambassador for the Duke of Urbino, who came to England to receive the Garter for his master.