Robert Ainslie may refer to:
Robert Ainslie (rugby union) (fl. 1879–1882), Scottish rugby union football player Sir Robert Ainslie, 1st Baronet (1730–1812), British ambassador to the Ottoman Empire, orientalist and numismatist Robert Ainslie (lawyer) (1766–1838), Scottish lawyer, writer and correspondent of Robert Burns Sir Robert Ainslie, 2nd Baronet of the Ainslie baronets (1777–1858)