The goals were scored by Lee Jeong-hyeop and Kim Young-gwon in either half to get their side into the final for the first time since 1988.
The Koreans did look the better side and did deserve their win.
South Korea made a positive start to the match and could have taken the lead inside five minutes as Han Gyo-won peeled away from Dhurgham Ismail, but failed to connect with Ki's pass.
Iraq nearly got caught out after 19 minutes as the dangerous Son broke forward.
With the defenders backing off he unleashed a powerful shot from 20-yards that Hachim was able to tip over the crossbar.
In the 20th minute the Koreans scored when Kim Jin-su delivered a free-kick into the penalty area that Lee glanced past Hachim from close-range to make the score 1-0.
In the second half South Korea continued with their attacking brand of football and five minutes into the second half Kim Young-gwon doubled the score.
Lee chested a high ball into the defender's path and he volleyed the ball, which took a deflection off Salam Shakir, on its way past Hachim and into the net to make the score 2-0.
The Koreans began to pepper the Iraq goal with chances with both Ki and Son unable to beat Hachim with efforts from outside the penalty area.
Iraq did have their fair share of chances in the second half.
Kalaf wasted a chance and Mahmood had two efforts to halve the deficit blocked by good defending.
In the end South Korea ran out 2-0 winners.