Qatar's Al Sadd overcame Suwon Bluewings 2-1 on aggregate despite losing the second leg of their semi-final 1-0 at home.
Jeonbuk qualified 5-3 on aggregate and the South Koreans will be confident of a second title following their 2006 success after another high-tempo attacking display saw off the Saudis.
"We got what we wanted, we are at home for the final and that is an advantage," Jeonbuk coach Choi Kang-hee told reporters. "Eninho's goals were a big help but we still had work to do."
Al-Ittihad's slim hopes of overturning the 3-2 first leg deficit at the World Cup stadium in Jeonju suffered an early blow when their leading striker Naif Hazazi was shown a red card in the 12th minute for head-butting Cho Sung-hwan.
Hazazi, who scored his side's two goals in the first leg, shoved a team-mate after the referee waved the red card, before collapsing to his knees in tears. Two other Saudi players had to help him from the field.
"The sending-off was another blow but there won't be any punishment for Hazazi. He is an excellent player and this kind of thing happens in football," Al-Ittihad coach Dimitri Davidovic said.
Jeonbuk flowed forward with wave after wave of attacks before Eninho scored a deserved second in the 36th minute direct from a corner. The Brazilian's inswinger went over Rashed Al Rahab at the near post and sneaked past goalkeeper Mabrouk Zaid.
In Doha, South Korea's Suwon sparked hopes of an unlikely turnround by taking the lead after just seven minutes at the air-conditioned Al Sadd stadium with a superb volley by Oh Jang-eun.
Al Sadd's former Asian Player of the Year Khalfan Ibrahim was impressive th
