Pollock, who appeared alongside Durham captain Dale Benkenstein at Natal and for South Africa, played in 108 Tests and 303 one-day internationals before retiring from international cricket in February.
The 34-year-old pace bowler, renowned for his accuracy, will join up with the Durham squad in June.
"When I got the offer from Durham I really jumped at the chance to get on board, they are determined to do well in the Twenty20 Cup and I want to contribute to that success," Pollock said in a statement.
"They proved themselves to be a force in the four-day and one-day game last year and I'm keen to help them replicate that success in the Twenty20 Cup," added Pollock, who captained South Africa from 2000-2003 after the corrupt Hansie Cronje was forced out and previously played county cricket for Midlands side Warwickshire.
Durham chief executive David Harker added: "Shaun is one of the biggest talents in world cricket and we're delighted that he's decided to join us. "He's got great experience in all formats of the game and we think he'll bring a great presence to the team, both on and off the field."
Pollock will also be commentating on this season's Test match and one-day international series between England and South Africa for Sky Sports television and BBC Radio Test Match Special.
Adam Mountford, the Test Match Special producer, said: "Having been so recently involved in the international game, and indeed still playing cricket at a high level, he (Pollock) will be able to provide a fascinating insight.
"We just hope he will give more away when he is commentating than he does when he is bowling!"
The son of former South Africa quick Peter and nephew of legendary batsman Graeme, Pollock is due to make his Durham debut on June 11 against Derbyshire at the Riverside.
Pollock, also a dangerous lower-order batsman, took 421 Test wickets at a low average of 23.11 apiece, taking five wickets in an innings on 16 occasions and 10 in a match once.
His batting, which perhaps never reached its full potential, saw Pollock score 3,781 Test runs at 32.31 with two hundreds.
In one-day internationals, Pollock took 393 wickets at 24,50 and scored 3,519 runs at 26.45.