Silja Kosonen

Silja Kosonen (born 16 December 2002) is a Finnish hammer thrower. She competed in the 2020 Summer Olympics. She won the hammer throw event at the Birmingham 2026 European Athletics Championships and the World U20 Championship held in Nairobi, Kenya.

Biography The daughter of Kimmo and Johanna Kosonen, she grew up in Raisio, in the Southwest Finland region. As a child, she participated in several sports, including football, orienteering, and other athletics events. At around the age of eight, she took up the hammer throw after her parents took her to try the event; in one of her first youth competitions, she immediately set a club record. Her family continued to support her athletic career, also helping to create training facilities on the family property.

After attending upper secondary school, she enrolled at the University of Turku, where she studied languages, with German as her main subject and English among her secondary subjects.

Openly gay, in 2026 she made public her relationship with Finnish futsal player Senni Viren, whom she met at the beginning of the year. Viren plays for RaiFu, a team based in Raisio, Kosonen's hometown, and has also been called up to the Finnish national futsal team.

Career She rose to international prominence already in the junior categories. At the age of 16, she won the gold medal in the hammer throw at the 15th European Youth Summer Olympic Festival in Baku 2019, setting a championship record with a throw of 72.35 m. In 2021, she won the gold medal in the hammer throw at the European U20 Championships in Tallinn, with a throw of 71.06 m. In the same year, she competed at the 2020 Summer Olympics in Tokyo, where she was eliminated in qualifying with a throw of 70.49 m, and at the World U20 Championships in Nairobi, where she won gold with 71.64 m, setting a championship record.

In 2022, she made her debut at the World Championships in Eugene, Oregon, finishing seventh in the hammer throw with 70.81 m after recording 72.15 m in qualifying. At the European Championships in Munich, she finished fifth with 69.45 m.

She won the bronze medal in the hammer throw at the European Games in Chorzów 2023, with a throw of 72.34 m, in an event that also counted towards the European Athletics Team Championships. A few months later, she won the gold medal at the European U23 Championships in Espoo, setting a championship record of 73.71 m. At the World Championships in Budapest, she finished fifth, improving her personal best to 73.89 m.

She finished fourth at the European Championships in Rome with a throw of 72.06 m. At the 2024 Summer Olympics in Paris, she improved her personal best to 74.04 m and finished fifth in the hammer throw.

In 2025, she finished fourth at the World Championships in Tokyo, setting a personal best of 75.28 m.

She won the first senior international title of her career at the 2026 European Championships in Birmingham, where she threw 76.28 m in the final of the hammer throw, finishing ahead of Italy's Sara Fantini and Norway's Beatrice Nedberge Llano.

Competition record