On 12 November 2020, in a Euro 2020 qualifying play-off against Scotland that ended in a 1–1 draw after extra time, Mitrović went on to take Serbia's fifth penalty and missed it as the penalty shoot-out ended 5–4 in Scotland's favour, thus denying his national team qualification for the tournament. On 27 March 2021, he scored Serbia's first goal in a 2–2 draw with Portugal, thereby surpassing the previous record of 38 goals by Stjepan Bobek, and becoming the highest goalscorer in the history of the national side.