From 30 July 2018 to October 2021[1] he served as Deputy Defence Minister, and headed the Main Military-Political Directorate of the Russian Armed Forces.

During this time he was a close associate of Valery Gerasimov and emphasized "preemption and asymmetric measures against expected NATO courses of action".

[11] On 5 October 2021, by decree of the President of Russia, Kartapolov was relieved of his post as head of the Main Military-Political Directorate and released from military service in connection with his transfer to work in the State Duma.

[12] On 18 March 2022 Kartapolov informed other members of the CSTO Parliamentary Assembly (PA) about Russian investigations of US involvement in Ukrainian biolabs.

[13] On 10 April 2023 as chair of the Defense Committee Kartapolov stated that soon-to-come legislative amendments would make it illegal to ignore electronic all military draft summonses.

If the legislation is passed, "it will limit draft evaders’ rights to drive a vehicle, buy and sell real estate, apply for credit, and leave the country.

[14] In July 2023, Kartapolov was responsible for new legislation which established regional military companies that will be in charge of "guarding the state border in times of war."

[15] Soon after his re-election to the 9th State Duma, Kartapolov praised Putin for his decision to remove as Minister of Defence Sergey Shoigu amid the spring 2024 general house-cleaning in the ministry and said: “The president does not make mistakes in personnel matters.”[16] On 24 June 2024 Kartapolov warned that Russia might change the doctrine for the application of nuclear weapons, to shorten the chain of command and thus to speed delivery.

[19] On 16 February 2015, the European Union included him in the sanctions list of persons whose assets are frozen in the EU and in respect of whom visa restrictions have been introduced.

The 53rd Anti-Aircraft Missile Brigade of the Air Defense belongs to the Western Military District, of which Kartapolov was the chief of staff at that time.

[23] According to statements published on the Bellingcat website, a check carried out by international experts showed that the data provided by Kartapolov was deliberately fabricated and no Ukrainian military aircraft were recorded in the vicinity of Boeing on the day of the crash.

[citation needed] On 26 September 2016, at a briefing by the Russian Ministry of Defense, Deputy Chief Designer of the Lianozovsky Electromechanical Plant Research and Production Association Viktor Meshcheryakov said that the Utyos T radar complex showed that there were no third-party air objects near the Malaysian aircraft.