2023–24 LEN Champions League Quarter-finals round

The 2023–24 LEN Champions League Quarter-finals round is played between 8 March and 15 May 2024 to determine the four teams advancing to the Final four of the 2023–24 LEN Champions League.

Format
The eight group winners and eight group runners-up were drawn into two groups, with each one containing two group winners and two group runners-up. In each group, teams will play against each other home-and-away in a round-robin format. The top two teams in each group advanced to the Final four.

Teams are ranked according to points (3 points for a win, 2 points for a penalty shootout win, 1 point for a penalty shootout loss, 0 points for a loss), and if tied on points, the following tiebreaking criteria are applied, in the order given, to determine the rankings:


 * Points in head-to-head matches among tied teams;
 * Goal difference in head-to-head matches among tied teams;
 * Goals scored in head-to-head matches among tied teams;
 * Goal difference in all group matches;
 * Goals scored in all group matches.

Draw
The draw took place in Barcelona on 15 December 2023. The seeded and unseeded clubs consist of the teams that finished first and second in the previous round respectively. The only restriction was that clubs from the same group in the Main round could not be drawn against each other.