Mari Pakarinen started playing the trumpet when she was eight years old at the North Kymi Music Institute, in Kouvola, Finland, with Karl-Heinz Hennen. Later she continued her studies at the Tampere Music Academy as a pupil of Aki Välimäki, graduating as a music teacher in 2014. In autumn 2015, Pakarinen began to study for a master's degree in the trumpet at the Sibelius Academy under Pasi Pirinen and Touko Lundell. She was principal trumpet with the Pori Sinfonietta from 2016-2017, co-principal cornetist with the Finnish Guards Band from 2012 to 2014, and leader of the Töölö Brass from 2012 to 2013. She has also played with the Ostrobothnia Brass Band and the Finnish Symphonic Wind Professionals, and played as soloist with the Pori Sinfonietta. Pakarinen is also founder member of the PowerBrassGirls ensemble and the Tampering Ensemble. She has played as soloist with the Pori Sinfonietta, the Polytech Orchestra and the Retuperä Voluntary Fire Brigade Band. Mari Pakarinen was selected as Young Artist of the Year at the Kymi Brass event in 2013. She has also taught trumpet at the Meri-Helsinki Music School since 2013.
Pakarinen is in the Young Chamber Musicians programme.