The Eurovision Song Contest 2021 is set to be the 65th edition of the Eurovision Song Contest. The contest will be held in Rotterdam, the Netherlands, following the country's victory at the 2019 contest with the song "Arcade" by Duncan Laurence. The Netherlands was due to host the 2020 contest, before it was cancelled due to the COVID-19 pandemic. It will be the fifth time that the Netherlands hosts the contest, having previously done so in 1958, 1970, 1976 and 1980.

Organised by the European Broadcasting Union (EBU) and host broadcasters Nederlandse Publieke Omroep (NPO), Nederlandse Omroep Stichting (NOS) and AVROTROS, the contest will be held at Rotterdam Ahoy and will consist of two semi-finals on 18 and 20 May, and the final on 22 May 2021. The EBU discussed carryovers between the 2020 and 2021 contests, and many participating countries allocated the same artists who were due to represent them in 2020. The three live shows will be hosted by Chantal Janzen, Edsilia Rombley, Jan Smit and Nikkie de Jager.

Thirty-nine countries will participate in the contest. Bulgaria and Ukraine will return after their absences from the 2019 contest, while Hungary and Montenegro will not return after their 2019 participation. Armenia and Belarus had originally planned to participate, but Armenia later withdrew due to social and political crises following the 2020 Nagorno-Karabakh war and Belarus was disqualified after their intended entry was found to be in violation of the contest's rules.