A bat used by Bradman in a tour of England in 1930 was sold for 29,375 pounds.
The cap went to a London-based Australian private collector, who intends to organise public viewings in Australia. The buyer of the bat is not known.
Christie's
associate director Rupert Neelands, a cricket specialist, described bidding for the cap as "frantic."
It had been expected to bring somewhere between 10,000 and 20,000 pounds but did much better. Ironically, experts thought the bat might make as much as 50,000 pounds.
Bradman, who averaged 99.94 in his 52-Test career, died in 2001 aged 92.