The Saudis went into the match at the Prince Mohammed bin Fahad Stadium desperately needing a positive result to keep alive their dwindling hope of a place at the London Games having drawn one and lost two of their previous three Group A matches.
The impasse ended on the hour mark when substitute Omar Suktan Khudari, who came on at the start of the second-half in place of Mohammed Salem Al Safri put the Saudis one up in the 60th minute.
Korean midfielder Kim Bo-kyung struck in the 90th minute to equalize for the Korea Republic.
Oman missed a late penalty as the Gulf Sultanate drew 2-2 with Qatar in their London 2012 third round qualifying match at the Al Sadd Stadium on Sunday.
Fahad Khalfan, who plays his club football for 2012 AFC Champions League qualifiers Al Rayyan, put the home side 1-0 up in the 27th minute only before Abdulaziz Al Maqbali to restore parity with 12 minutes of the first-half left to play.
The visitors took the lead in the 75th minute courtesy of Mohammed Saleh Al Musalami only for Qatar to level with a penalty four minutes from full-time through skipper Hassan Al Haydos.
