In 2011, he joined the Headquarters of the European People's Party (EPP) as Political Advisor for Economics and Social Policy.

[7] In March 2014, Mureșan joined the People's Movement Party (PMP), and took part in the European Parliament elections which were held on 25 May 2014.

[3] The European Parliament approved Mureșan's report on redundancies from Câmpia Turzii in September 2014, allocating EUR 3.57 million in European Globalisation Adjustment Fund that were needed in order to offer support to redundant workers from Mechel Steel Plant from Câmpia Turzii.

[9] In July 2015, the Parliament approved financial aid worth EUR 66.5 million in order to compensate the damage caused by the floods of 2014 in Romania, Italy and Bulgaria in response to a report coordinated by Mureșan.

[13] Mureșan participated as a European Parliament representative at the 2016 World Bank-IMF annual meeting in Washington DC.

"[18] On 24 September 2018, Mureșan submitted to the National Liberal Party (PNL) his application file as candidate for a new mandate in the European Parliament.

At the same time, he emphasized his commitment to obtain sufficient financial allocations from the EU Budget for "Erasmus" scholarships and researchers, as well as for farmers and cohesion policy.

Mureșan also outlined his plans to actively take part in the debates on the future of the Eurozone, so that the decisions adopted at EU level would not affect in a negative way the economy of Romania.

On 14 March 2019, the enlarged presidency of the National Liberal Party (PNL) approved the list of candidates for the European Parliament elections taking place on 26 May 2019.

[20] On 27 March 2019, the National Liberal Party officially submitted to the Central Electoral Bureau the list of candidates and the necessary support signatures for the European Parliament elections, taking place on 26 May 2019.

[26] The report on the Sustainable Europe Investment Plan (the Green Deal), coordinated by Mureşan, was adopted in October 2020 in a joint session of the European Parliament's Budgets and Economic and Monetary Affairs Committees.

The Report recommends the use of unspent funds from the Recovery and Resilience Facility, about EUR 200 billion, for investments in cross-border energy projects.

Mureșan's report, which supports Croatia's accession to the Eurozone, was adopted by the European Parliament's plenary in July 2022.