The cap was awarded after his appearance for England against Portugal in a 3-0 win at the National Stadium, Lisbon, on May 14, 1950.
It will now take its proud place alongside the recently-acquired double-winning medals of Dave Mackay in our proposed new museum.
Sir Alf made 250 apprearances for us between 1949-55 and was a member of our famous 'push and run' side that clinched the Second Division and then First Division Championships back-to-back in 1950 and 1951.
Born in Dagenham, Essex, in 1920, Sir Alf began his playing career at Southampton before his move to Tottenham.
He won 32 England caps in total, scoring three goals and after ending his playing career kicked-off his managerial days at Ipswich Town.
Sir Alf took the small club from Division Three also-rans to Division One champions in 1962 before taking on the England job and, most famously, winning the World Cup in 1966.
Unfortunately he died in 1999, aged 79.
The club has bought one of Sir Alf Ramsey's England caps in an auction of the Lane and England legend's football memorabilia at Christie's.