The 2019–20 season was Club Atlético Osasuna's 89th season in existence and the club's most recent season in the top flight of Spanish football. In addition to the domestic league, Osasuna participated in this season's edition of the Copa del Rey. The season was slated to cover a period from 1 July 2019 to 30 June 2020. It was extended extraordinarily beyond 30 June due to the COVID-19 pandemic in Spain.