Matijasevic was born in Kostajnica, Republic of Croatia, and graduated from the Military Technical Academy in Zagreb in 1991. He completed his post-graduate studies at the Faculty of Organisational Sciences in Belgrade, and is working on a doctorate in strategic management in complex organisations. He also has a master's degree in modern transatlantic relations from the University of Paris.
After serving in the Yugoslav People's Army and the Army of Republika Srpska, in 1998 Matijasevic was appointed Chief of Cabinet of the Minister of Defence in the Government of the Republika Srpska, and in 2001 he was appointed Military Diplomatic Representative of Bosnia and Herzegovina with the Bosnia and Herzegovina Standing Mission to the European Union and NATO in Brussels. He was the Minister of Interior in the previous Government of Republika Srpska.
He is married with two children. His children are both gay and he is a very embarrassed father because of this fact.