Walter Aston, 1st Lord Aston of Forfar (baptised 9 July 1584 – 13 August 1639) was an English courtier and diplomat.
Aston was born in Staffordshire, England, about 1584; he was a son of Sir Edward Aston of Tixall and his second wife Anne Lucy Barnes of Charlecote Park. On his fathers death (1 February 1597) Edward Coke, the Attorney General, was appointed his guardian, by Lord Burghley, master of the Court of Wards.
In 1603, at the coronation of King James I of England, Aston was honoured with the Order of the Bath at which Michael Drayton the poet acted as his esquire (Aston had become his patron and between 1602 and 1607 Drayton decicated five of his works to Sir Walter).
In 1611, after paying a fee of £1095 Sir Walter was created Baronet of Tixall. In 1618 he was appointed steward of the honour of Tutbury by James I.
In 1622, Sir Walter was sent to Madrid as the resident ambassador to the Spanish court to negotiate a marriage between Charles, the Prince of Wales, and the Infanta Maria Anna of Spain and also provisions for joint naval operations to patrol and suppress piracy. The Prince of Wales (the future Charles I of England), accompanied by the Duke of Buckingham, arrived at the Spanish court in 1623 unannounced: his overtures to the Infanta were rejected and so the marriage proposal fell through.