2019 AFC Champions League knockout stage
The 2019 AFC Champions League knockout stage was played from 18 June to 24 November 2019. A total of 16 teams competed in the knockout stage to decide the champions of the 2019 AFC Champions League.
Qualified teams
The winners and runners-up of each of the eight groups in the group stage advanced to the round of 16, with both West Region and East Region having eight qualified teams.| Region | Group | Winners | Runners-up |
| West Region | A |  Zob Ahan |  Al-Nassr |
| West Region | B |  Al-Wahda | Al-Ittihad |
| West Region | C | Al-Hilal |  Al-Duhail |
| West Region | D | Al-Sadd | Al-Ahli |
| East Region | E |  Shandong Luneng |  Kashima Antlers |
| East Region | F | Sanfrecce Hiroshima | Guangzhou Evergrande |
| East Region | G |  Jeonbuk Hyundai Motors | Urawa Red Diamonds |
| East Region | H | Ulsan Hyundai | Shanghai SIPG |
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 is played on a home-and-away two-legged basis. The away goals rule, extra time and penalty shoot-out were used to decide the winner if necessary.
Schedule
The schedule of each round is as follows. Up to the semi-finals, matches in the West Region were played on Mondays and Tuesdays, while matches in the East Region were played on Tuesdays and Wednesdays.| Round | First leg | Second leg |
| Round of 16 | 18–19 June 2019, 5–6 August 2019 | 25–26 June 2019, 12–13 August 2019 |
| Quarter-finals | 26–28 August 2019 | 16–18 September 2019 |
| Semi-finals | 1–2 October 2019 | 22–23 October 2019 |
| Final | 9 November 2019 | 24 November 2019 |
Bracket
The bracket of the knockout stage was determined as follows:| Round | Matchups |
| Round of 16 | ;West Region
|
| Quarter-finals | ;West Region
|
| Semi-finals | ;West Region
|
| Final |
|
The bracket was decided after the draw for the quarter-finals, which was held on 2 July 2019, 16:00 MYT, at the AFC House in Kuala Lumpur, Malaysia.
Round of 16
Summary
In the round of 16, the winners of one group played the runners-up of another group from the same region, with the group winners hosting the second leg, and the matchups determined by the group stage draw.
West Region
Al-Nassr won 4–3 on aggregate.----
Al-Ittihad won 6–4 on aggregate.
----
Al-Sadd won 4–2 on aggregate.
----
Al-Hilal won 4–3 on aggregate.
East Region
3–3 on aggregate. Kashima Antlers won on away goals.----
4–4 on aggregate. Guangzhou Evergrande won 6–5 on penalties.
----
Urawa Red Diamonds won 4–2 on aggregate.
----
2–2 on aggregate. Shanghai SIPG won 5–3 on penalties.
Quarter-finals
Summary
The draw for the quarter-finals was held on 2 July 2019. In the quarter-finals, the four round of 16 winners from the West Region played in two ties, and the four round of 16 winners from the East Region played in two ties, with the matchups and order of legs decided by draw, without any seeding or country protection.
West Region
Al-Sadd won 4–3 on aggregate.----
Al-Hilal won 3–1 on aggregate.
East Region
3–3 on aggregate. Urawa Red Diamonds won on away goals.----
1–1 on aggregate. Guangzhou Evergrande won on away goals.
Semi-finals
Summary
In the semi-finals, the two quarter-final winners from the West Region played each other, and the two quarter-final winners from the East Region played each other, with the order of legs determined by the quarter-final draw.
West Region
Al-Hilal won 6–5 on aggregate.East Region
Urawa Red Diamonds won 3–0 on aggregate.Final
In the final, the two semi-final winners played each other, with the order of legs reversed from the previous season's final.
Al-Hilal won 3–0 on aggregate.