Needing three points to guarantee at least third place in Group B and a play-off spot, Iran took a huge step towards their goal when Moasoud Shojaei broke the deadlock after 50 minutes.
But Park found the back of the net nine minutes from time with a clinical finish following a neat one-two with Kim Jung-woo to keep the Koreans` unbeaten record in the final qualifying phase intact.
A low-key opening 45 minutes came to life as it drew to a close when Javad Nekounam curled a free-kick just past Lee-Won-jae's near post.
The Korean keeper was called into action again shortly after when Shojaei capitalised on some sloppy play to bundle his way through, only for Lee to turn his effort behind at full stretch to his left.
The second half proved far more entertaining and the visitors took the lead five minutes after the interval.
Shojaei threw himself at Mohammad Nosrati's dangerous inswinging delivery from the left wing, and although the cross just evaded the midfielder, Lee Won-jae punched the ball against the midfielder and it bounced into the unguarded net.
Shojaei then narrowly failed to apply a finish to a loose ball following a free-kick, before Park Chu-young was set free at the other end and he beat two defenders only to see Mehdi Rahmati save his low effort with his legs.
Korea cranked up the pressure and Park Chu-young came within inches of an equaliser in the 65th minute.
Nekonam brought down Lee Keun-ho on the edge of the box and the Monaco striker saw his exquisite right-footed free-kick smack the inside of the post with Rahmati a mere spectator, although the Iran keeper did well to parry Lee Cheun-yo's fierce drive from the follow-up.
The hosts deservedly levelled in the 81st minute, however, as Park Ji-sung fired the ball into Kim Jung-woo and collected the return before drilling low past Rahmati and inside the near post.
Korea, who had already qualified for South Africa, almost grabbed a winner in the last minute when Kim Jung-woo's beautiful dummy allowed substitute Cho Won-hee to burst into the box.
He rounded Rahmati but lost control of the ball under his feet and shinned it wide.