In the match held at the Bahrain National Stadium in Riffa on Monday, Sardar Azmoun opened the scoring for the visiting team in the 51st minute.
Azmoun made it 2-0 on the hour mark after receiving a good pass from Taremi.
Everyone wanted to draw Qatar, the host and by a gulf the gentlest prospect of the top seeds.
The national squad tops Group C with 12 points, while third placed Iran has collected nine points.
The national team have never lost to Iran at home.
Bahrain even beat Iran in the 2002 World Cup qualifiers and drew in the 2006 World Cup qualifiers.