As part of £3 million overall spending cuts, the Queen's expenditure on IT fell from £400,000 in 2008 to £200,000 last year.
But the Palace expects spending to rise again this year, to £300,000. No details were given on the rise in costs.
Last year, one of the principal items of IT expenditure was the main control panel for the automatic fire detection systems, and related computers, which were replaced at Windsor and Buckingham Palace, this year's Civil List report shows.
The Palace also offers specialist IT training for staff, and has developed e-learning resources.
The Queen is cutting spending across the board, on items ranging from furniture to staff pay and travel. She was forced to take a record £6.5 million from cash reserves last year, leaving a £15.2 million left.
Sir Alan Reid, Keeper of the Privy Purse, said: "The Royal Household is acutely aware of the difficult economic climate and took early action to reduce its Civil List expenditure by 2.5 per cent in real terms in 2009.
"We are implementing a headcount freeze and reviewing every vacancy to see if we can avoid replacement."
In last month's Emergency Budget, Chancellor George Osborne said that the Palace funding, known as the Civil List, would be frozen for a year at £7.9 million.