Member of the Presidium of the General Council of the United Russia Party.

Belinsky Penza State Pedagogical University 2001–2004 Deputy Head of the Zheleznodorozhny District Administration of Penza for Social Policy and Cooperation with Law Enforcement Agencies 2004–2006 Specialist expert of the Office of the Plenipotentiary Representative of the President of the Russian Federation in the Far Eastern Federal District 01.2006–11.2006 Head of the Public Relations Department of the Government of the Penza Region 11.2006–01.2007 Head of the Department for National Policy Issues, Relations with Public and Religious Associations of the Government of the Penza Region 01.2007–04.2007 Advisor to the Office of the Plenipotentiary Representative of the President of the Russian Federation in the Volga Federal District 04.2007–01.2008 Minister of Education and Science of the Penza Region 01.2008–06.2008 Vice Governor of the Penza Region 06.2008–03.2009 Deputy Chairman of the Government of the Penza Region 03.2009–04.2009 Deputy Prime Minister–Head of the Department for Information Policy and Mass Media of the Penza Region 04.2009–09.2013 Assistant to the Plenipotentiary Representative of the President of the Russian Federation in the Volga Federal District 09.2013–09.2017 Deputy Plenipotentiary Representative of the President of the Russian Federation in the Volga Federal District Full State Counsellor 2nd Class of the Russian Federation.

[6] Since December 2017 he has been Member of the Presidium of the General Council of the All-Russian Political Party "United Russia" Since December 2017 he has been Chairman of the All-Russian Council of Local Self-Government Since May 2019–First Deputy Chairman of the Supreme Council of the All-Russian Association for the Development of Local Self-Government.

On 26 March 2021 President of Russia Vladimir Putin appointed Oleg Melnichenko Acting Governor of the Penza region, prior to taking office of the person elected governor of the Penza region.

[8][9] In response to the Russian invasion of Ukraine, the Office of Foreign Assets Control of the United States Department of the Treasury added Melnichenko to the Specially Designated Nationals and Blocked Persons List on 24 February 2023, which results in his assets being frozen and U.S. persons being prohibited from dealing with him.