Team Melli had previously beated Palestine 4-1 and Hong Kong 1-0 in the group.
In the match held at the Education City Stadium in Al Rayyan, Qatar, on Tuesday, Mehdi Taremi scored twice in each half.
The Porto striker opened the scoring for Iran in the 25th minute, moving behind the Emirati defense to take advantage of an intelligent Sardar Azmoun pass before coolly slotting home.
Iran’s star duo Azmoun and Taremi combined again to make it 2-0 in the 65th minute when the AS Roma forward cut inside and fed his teammate with a well-weighted pass and Taremi emphatically converted into the roof of the net to double Team Melli’s advantage.
The UAE could reduce the deficit in the 64th minute but Iran goalkeeper Alireza Beiranvand saved Yahya Al Ghassani’s penalty kick.
Al Ghassani pulled a goal back in the added time.
Iran will meet Syria on Jan. 31, while the UAE face Tajikistan three days earlier.
Palestine also reached the Asian Cup knockout rounds for the first time after beating Hong Kong 3-0 on Tuesday for their maiden win in the history of the competition.
