Dimitri Soudas has been given the job of the party's executive director.
A Conservative party source tells The Canadian Press that the decision was made Friday night at a meeting of party brass at 24 Sussex Drive.
Soudas confirmed the appointment, but declined an interview request, saying it was no longer his role to take questions from the media.
He accepted many congratulations on Twitter and tweeted that it — quote — “Always feels good to be back home with family.”
Soudas was a high profile member of Harper's communications team from 2006 to 2011, before he left government to head communications at the Canadian Olympic Committee.
Soudas is the latest of Harper's insiders to get a key job.
The prime minister named Ray Novak as chief of staff last May to replace Nigel Wright, who was a casualty of the Senate expense scandal.
Another longtime associate of Harper, Jenni Byrne, is deputy chief of staff.
Soudas was known for an often acrimonious relationship with the media when he was heading Harper's communications efforts.
He also ran into controversy last year when his name surfaced in connection with the appointment of a chief executive at the Montreal Port Authority in 2007.
The chairman of the port's board said he and other directors met Soudas at a Montreal restaurant and that Soudas pressed the candidacy of a man caught up in Quebec's corruption inquiry.
In the end, the man never got the job, and Soudas has disputed the meeting took place.