Arno Lietha (born 20 November 1998) is a Swiss ski mountaineer. He will rerepsent Switzerland at the 2026 Winter Olympics.
Lietha began his career in alpine skiing before switching to ski mountaineering at 16 years old. He competed at the 2019 World Championship and won a gold medal in the sprint race.
He won the World Cup sprint crystal globe three consecutive years from 2021 to 2023.