[2][3] He was frontrunner for the Alternative for Germany (AfD) party at the 2016 Baden-Württemberg state election and was a Member of Parliament and parliamentary leader from March 2016.

[5] He served as federal spokesman for, and thus leader of, the AfD from July 2015 until his resignation in January 2022, caused by conflict with right-wing extremist elements in the party.

[11] In September 2019, the regional film fund HessenFilm [de] fired its CEO Hans Joachim Mendig over a controversial meeting with Jörg Meuthen.

[14] Meuthen was initially considered part of the Bernd Lucke-related, more economically liberal and moderate wing of the AfD near the start of the party's founding.

During an AfD party conference in 2016, he stated "We are opposed to allowing immigration in such large numbers with open eyes that we will no longer recognize our own country in just a few years.

[26] He justified this with the fact that he had lost the power struggle with the formally dissolved right-wing extremist "Der Flügel" ("the wing") over the political direction of AfD.

Meuthen criticized that the party had developed far to the right and was in large parts no longer concurrent with the liberal democratic basic order in Germany.

In the interview, he stated that he confided in Marine Le Pen on how to remove extremist elements from the party, but said that expelling controversial members of the AfD was more difficult due to German law on the matter.

He also claimed to have voted against expelling Björn Höcke to avoid dividing the party and believed that the Der Flügel wing would not gain popularity due to voters seeing it as too extreme, but later felt this decision was "a complete error.” Meuthen claimed that he ultimately quit the party after he was unable to fire a senior member of the AfD's federal board who had praised national socialism and said that while Germany still needed much stronger policies to deal with immigration, Islamism and the EU, the AfD would be unable to wield any influence in these areas even with strong support due to the other parties refusing to make deals with it.