Sir Rudolph Edgar Francis de Trafford, 5th Baronet, OBE (31 August 1894 – 16 August 1983) was a British aristocrat and banker who succeeded his brother to the de Trafford baronetage at the age of 77.
Rudolph was the second son of Sir Humphrey de Trafford, 3rd Baronet and Violet Alice Maud Franklin. He attended Downside (Sep 1907 to Jul 1911), and Trinity College, Cambridge, where he was friends with Marshall Field III. After graduating with a BA in 1915, he fought in the First World War, being twice mentioned in despatches. In 1919, Rudolph joined Marshall Field in California for a vacation with Field's wife and children on Catalina Island.
By 1931, Rudolph was working in London for the Boston investment bank Lee, Higginson & Co., which had also employed Marshall Field III. Although the bank collapsed in the Swedish match scandal in 1932, Rudolph continued to work for reformed company. In his capacity as the senior director in Europe of Higginson and Co, he negotiated at least two unsuccessful attempts at merger with the British investment house Kleinwort Benson in 1936 and 1938.
Rudolph married June Isabel Chaplin, daughter of Lieutenant-Colonel Reginald Chaplin (son of John Worthy Chaplin VC), at St James's, Spanish Place on 6 February 1924. The reception was held at Seaford House, which was lent to the couple by Lord and Lady Howard de Walden and they honeymooned in Egypt. Their only son, Dermot, was born on 19 January 1925.