Together with Karin Oberhofer, Dominik Windisch and Lukas Hofer she won a bronze medal in the Mixed relay at the 2014 Winter Olympics, in Sochi, Russia.

At the 2018 Winter Olympics in Pyeongchang, South Korea she won again the bronze medal in the Mixed relay with Lisa Vittozzi, Lukas Hofer and Dominik Windisch.

At the 2019 Championships in Östersund, she won the gold medal in the 12.5 km Mass Start, also a first for Italian women in Biathlon.

In February 2019, Wierer became the third biathlete (after French Martin Fourcade and Marie Dorin Habert) to achieve a victory in every[B] biathlon discipline.

12 medals (4 gold, 5 silver, 3 bronze) Notes about WC results During Wierer's career, until 2023 the World Championships results counted for the World Cup of that season, starting from that season they did not anymore.