The appointment follows the confirmation that team principal John Booth and president and sporting director Graeme Lowdon will depart at the end of the season.
Ryan, who joins with immediate effect, has over three decades of Formula One experience, having most recently worked for McLaren where he served as sporting director before his departure in 2009.
In his new role Ryan will oversee race team operations, with a particular eye on the squad’s transition to Mercedes power for 2016.
“I’m delighted to announce Dave’s appointment,” said Marussia owner/investor Stephen Fitzpatrick. “He needs no introduction, of course, having spent 34 years within the sport contributing to an incredible tally of race and championship wins.
“Along with our new Mercedes Benz power unit, technical partnership with Williams and recent additions to the design and technical team, Dave's arrival is another important step towards our goal of creating a truly competitive racing team.
“I am also able to confirm that John Booth and Graeme Lowdon will be leaving the team at the end of the current season. I have the utmost respect for them as individuals and for all they have achieved, both with this team and in their long careers in motorsport, and I would like to take this opportunity to thank them for their hard work and dedication during this season in particular. Like every great story, there comes a time to start a new chapter.”
Ryan, who has run his own sportscar team for the last six years, said he was excited to be joining Marussia at a pivotal time in their development.
“Having spent time with Stephen, and understood his vision for the future, it is clear he has ensured there is a strong platform from which the team can make big steps forward in the seasons ahead," he said.
“Manor has all the hallmarks of a fiercely competitive racing team, but having grown up in a much more contemporary Formula One era, it is a very lean operation with a collaborative culture, which leaves it well placed to contend with the sport’s future direction. There is clearly a big challenge ahead and a lot of work to do, but I can’t wait to meet the wider team and get down to business.”
Marussia are currently 10th in the constructors’ standings, having failed to register any points. Their best result since joining the F1 grid as Virgin Racing in 2010 remains Jules Bianchi’s ninth-place finish at Monaco in 2014.