On August 8, 2002 Mammadov was appointed the Minister of Transportation of Azerbaijan Republic by Presidential Decree No.

[1] According to the New Yorker, in 2014, "Mammadov, a career government official, had a salary of about twelve thousand dollars, but he was a billionaire.

"[1] During his time as Transportation Minister, road construction cost Azerbaijan $18 million per kilometer, which was the most in the world by one estimate.

An offer by Bechtel, an American contractor, to build roads at a cost of $6 million per kilometer were rejected.

[1] In his role as Transportation Minister, Mammadov established close relationships with the Darvishis, an Iranian family that has leadership positions in the Revolutionary Guard.

He is the member of the International Transport Academy and Honorary Citizen of Derbent city of Russian Federation.