Gareth Davis, a non-executive director of DS Smith since June 2010 and acting chairman since October 2011, has succeeded Johnson as chairman of the board and of the nominations committee with immediate effect.
Davis was previously group chief executive of Imperial Tobacco and is chairman of both Wolseley, the world’s largest trade distributor of plumbing and heating products, and gaming and sports betting firm William Hill.
In a statement to the stock exchange, Matthew Jowett, group general counsel and company secretary, said that the board had "for some time been planning for [Johnson's] retirement during 2012".
Chris Bunker, senior non-executive director of DS Smith, said: "On behalf of the board and the company, I would like to thank Peter for his immeasurable contribution to DS Smith. He has led the business through a period of transformation, and the business is in an excellent position to grow and develop further as a result.
"The board is delighted that Gareth has agreed to succeed him as chairman and lead the company through this next exciting stage of growth."
Meanwhile, DS Smith also confirmed that it had completed the disposal of its European office products wholesale business Spicers, announced last July, to Spanish stationery supplier Unipapel on 30 December 2011.
DS Smith said that it had recorded net proceeds, after tax and related costs, in the region of £160m on the sale of the £200m division. Following the sale, the company is now focused on its recycled packaging business.