The 2023–24 EHF Champions League was the 64th edition of Europe's premier club handball tournament, running from 13 September 2023 to 9 June 2024.

Matches were played in a double round-robin system with home-and-away fixtures, fourteen in total for each team.

The knockout stage included four rounds: the playoffs, quarter-finals, and a final-four tournament comprising two semifinals and the final.

The eight quarterfinalist teams were paired against each other in two-legged home-and-away matches, with the four aggregate winners qualifying to the final-four tournament.

[5][6] The fixed place for Russia was vacant since the country and its clubs were not admitted to participate in the EHF competitions due to the Russian invasion of Ukraine.