His appointment follows the recent arrival of new chief executive Barry McIlheney and the departure of previous chairman Peter Phippen, managing director of BBC Magazines.
Reed said: "I am delighted and honoured to take over this prestigious position and I thank Peter for all his hard work in starting the revitalisation of the PPA – a mission that I intend to carry forward with vigour."
The arrival of Reed appears to mark the conclusion of the restructure that was initiated by the sudden departure of former chief executive Jonathan Shepherd late last year.
This led to the arrival of Eric Verdon-Roe, previously managing director of Haymarket Media Group, as a consultant.
Following Verdon-Roe's review of the PPA, a new "more accountable" management structure has been put in place, in order to "better serve the needs of the PPA membership and the market it serves".