The audience was the highest for the channel in over 10 years.
The ceremony was opened by Professor Stephen Hawking who took viewers on an “exquisite journey of discovery” and urged spectators to look upwards at the stars and ‘be curious’. The show also featured appearances from Sir Ian McKellen.
The average audience across the four and a quarter hour show was 7.6 million, a 40 percent share of the television audience.
BBC One’s coverage of the 2008 Beijing Paralympics opening ceremony peaked at 2.8 million.
Commenting on the viewing figures, Channel 4’s Chief Creative Officer, Jay Hunt said: “Last night’s opening ceremony was a spectacular start to the London 2012 Paralympic Games and I’m delighted that so many viewers enjoyed it with us.
“It kicks off eleven days of great sporting coverage on Channel 4.”
The broadcaster has promised an “unprecedented” level of Paralympic Games coverage across multiple platforms including three live streams available on Freesat, Sky and Virgin Media.