The network was understood to have bid in the region of £5m for the slot, which was made available by transmission company Crown Castle after additional broadcast capacity was added to the free-to-air digital service.
ITV chief executive Charles Allen said: "One of our strategic objectives is to grow ITV's successful multichannel business and we are therefore delighted to have secured additional capacity on this platform."
ITV will relaunch the Granada/Sky Broadcasting-owned channel Men & Motors as ITV4, offering cars, sport and adult entertainment for a 16- to 34-year-old male audience.
ITV4 will launch later this year and is initially tied into a 12-month contract with Freeview, which is owned by Crown Castle, the BBC and BSkyB.
Channel 4 has won the second available slot which will not be available until summer 2005.
The broadcaster is now mulling whether to launch either: entertainment channel E4; new channel More 4; gaming channel 9 Live, which it trialled on E4 last year; or a film channel with the BBC.
During the bidding process, which has been heavily contested for the last three months, Crown Castle reportedly turned down bids from Five, Disney, Turner Broadcasting, Sit-Up TV and Top-Up TV.
It also said there will be no more Freeview slots on the channel for some time.
A slot on Freeview when it launched in October 2002 was originally worth £1m but because space is limited and digital terrestrial TV take-up has soared, the new slot is worth in excess of £5m.
If you have an opinion on this or any other issue raised on Brand Republic join the debate in the .