Pardew, assistant John Carver, coach Steve Stone and goalkeeping coach Andy Woodman have all been given identical deals with chief scout Graham Carr having signed his own eight-year contract in June.
The announcement represents a huge vote of faith in Pardew and his staff with the 51-year-old having initially taken over from the sacked Chris Hughton in December 2010 on a five-year deal which few expected him to see out at the time.
Pardew has presided over a remarkable rise since launching his career on Tyneside with a 3-1 home victory over Liverpool.
He was appointed after Ashley and managing director Derek Llambias decided Hughton, who dragged the club back into the Barclays Premier League in the wake of relegation at the end of the 2008-09 campaign, had taken the Magpies as far as he could.
The former Reading, West Ham, Charlton and Southampton manager kept them in the top flight at the end of their first campaign back there, and then paved the way for a remarkable second season.
Against all the odds, Newcastle finished fifth in the league in May to secure a return to European football after an absence of five years.
Indeed, they were only five points shy of qualifying for the Champions League for just the third time in their history.
Pardew has built upon the spirit instilled by Hughton during his time at the helm, and astute signings - he has brought in the likes of Yohan Cabaye, Demba Ba and Papiss Cisse with great success - with the help of Carr have helped to restore optimism at a club which had been through years of turmoil.
He has done his job to such good effect that fans furious at both Hughton's dismissal and Pardew's arrival have since taken him to their hearts, and the news will be welcomed by many.
However, there is much work still to be done, and with Ashley insisting that the club must be run along strict financial lines, the manager knows his acumen and that of his staff, coupled with the efforts of his players, rather than heavy investment in the squad will be the way forward.
The one issue he would dearly love to address during the terms of his deal is the trophy drought which has left Tyneside hungry for tangible success for 43 years.
A weakened Newcastle side slipped out of the Capital One Cup at the hands of a weakened Manchester United side at Old Trafford on Wednesday night as another opportunity went begging, and while Pardew admits that qualifying for the Champions League would be as significant as winning a trophy, he is aware of the desire to end that miserable record.
Llambias revealed the club had made the move to try to establish the same kind of stability on Tyneside as has been enjoyed by Manchester United and Arsenal under Sir Alex Ferguson and Arsene Wenger respectively.
He said: "If you look at clubs like Manchester United and Arsenal, Sir Alex Ferguson and Arsene Wenger have shown that stability gives you the best platform to achieve success and that is the model we wish to emulate here.
"We are looking to build on the success we had last season and these new contracts are aimed at keeping the club progressing on and off the pitch, as we have done since returning to the Premier League in 2010.
"Alan has done a fantastic job over the last couple of years and has proved what a great Premier League manager he is.
"I have total respect for him in all football matters and have an excellent relationship with him which I think benefits the club enormously.
"Alan also has one of the best backroom teams in the country and I would like to thank John Carver, Steve Stone, and Andy Woodman for all their combined efforts.
"We hope this announcement will be great news for the fans, whose support and commitment to this club over the years has been fantastic."