2023–24 AFC Champions League knockout stage

The 2023–24 AFC Champions League knockout stage began on 13 February with the round of 16 and ended on 25 May 2024 with the final to decide the champions of the 2023–24 AFC Champions League. A total of 16 teams competed in the knockout stage.

Qualified teams
The group winners and three best runners-up in the group stage from each region advanced to the round of 16, with both West Region (Groups A–E) and East Region (Groups F–J) having eight qualified teams. 

Format
 In the knockout stage, the 16 teams played a single-elimination tournament, with the teams split into the two regions until the final. Each tie was played on a home-and-away two-legged basis. Extra time and a penalty shoot-out were used to decide the winner if necessary (note that the away goals rule had been abolished) (Regulations Article 10.1). The order of matches (home vs away) was determined at the draw, except for the final. The final was pre-determined on a rotation basis, with the first leg hosted by the team from the East Region. The match-ups were determined at a single draw event, made on 28 December 2023.

Schedule
The schedule of the competition was as follows.

Bracket
The bracket was decided after the draw for the knockout stage, which was held on 28 December 2023, 16:00 MYT (UTC+8), at the AFC House in Kuala Lumpur, Malaysia. 

Summary
 The first legs were played on 13–15 February, and the second legs were played on 20–22 February 2024.


 * +West Region


 * +East Region


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West Region
Al Ain won 2–1 on aggregate.

Al Nassr won 3–0 on aggregate.

Al Hilal won 6–2 on aggregate.

Al-Ittihad won 2–1 on aggregate.

East Region
Jeonbuk Hyundai Motors won 3–1 on aggregate.

Ulsan Hyundai won 5–1 on aggregate.

Shandong Taishan won 6–5 on aggregate.

Yokohama F. Marinos won 3–2 on aggregate.

Summary
 The first legs were played on 4–6 March 2024, and the second legs were played on 11–13 March 2024.


 * +West Region


 * +East Region


 * }

West Region
4–4 on aggregate; Al Ain won 3–1 on penalties.

Al Hilal won 4–0 on aggregate.

East Region
Ulsan Hyundai won 2–1 on aggregate.

Yokohama F. Marinos won 3–1 on aggregate.

Summary
 The first legs were played on 17 April, and the second legs were played on 23 and 24 April 2024.


 * +West Region


 * +East Region


 * }

West Region
Al Ain won 5–4 on aggregate.

East Region
3–3 on aggregate; Yokohama F. Marinos won 5–4 on penalties.

Final
 The East Region team hosted the first leg as pre-determined on a rotation basis.


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 Al Ain won 6–3 on aggregate.