Sir Ralph George Elphinstone Mortimer (7 July 1869 – 3 May 1955) was an English landowner and public servant who had a fleeting career as a first-class cricketer. He was a right-handed batsman who played for Lancashire. He was born in Newcastle upon Tyne, Northumberland and died in Milbourne Hall, near Ponteland, Northumberland.
As a cricketer, Mortimer made just one first-class appearance for Lancashire, in a University match against Oxford University in 1891. In the only innings in which he batted, he scored 22 not out. But he remained a player at a lower level and, representing Northumberland, he played in the Minor Counties Championship from 1896 to 1906; he later served as president and chairman of the cricket club.
Mortimer studied at Harrow School and Trinity College, Cambridge. In 1891, he inherited Milbourne Hall from a maternal relative and thereafter was occupied with good works in the Northumberland area. He was involved from early days with the Boy Scout movement and was chairman or vice-chairman of Newcastle Royal Victoria Infirmary for 36 years; at the age of 72, The Times reported in his obituary, he was involved in more than 50 local committees. He was awarded the OBE in 1920 and knighted in 1934.