2017 AFC Champions League knockout stage
The 2017 AFC Champions League knockout stage was played from 22 May to 25 November 2017. A total of 16 teams competed in the knockout stage to decide the champions of the 2017 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 |  C.|Al-Ahli] |  Esteghlal |
| West Region | B |  Lekhwiya | Esteghlal Khuzestan |
| West Region | C | Al-Ain |  Al-Ahli |
| West Region | D | Al-Hilal | Persepolis |
| East Region | E |  Kashima Antlers |  Muangthong United |
| East Region | F | Urawa Red Diamonds |  Shanghai SIPG |
| East Region | G | Kawasaki Frontale | Guangzhou Evergrande |
| East Region | H | Jiangsu Suning |  Jeju United |
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. The away goals rule, extra time and penalty shoot-out were used to decide the winner if necessary.
Schedule
The schedule of each round was as follows. 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 | 22–24 May 2017 | 29–31 May 2017 |
| Quarter-finals | 21–23 August 2017 | 11–13 September 2017 |
| Semi-finals | 26–27 September 2017 | 17–18 October 2017 |
| Final | 18 November 2017 | 25 November 2017 |
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 knockout stage, which was held on 6 June 2017, 16:00 MYT, at the JW Marriott Hotel Kuala Lumpur in Kuala Lumpur, Malaysia.
Round of 16
In the round of 16, the winners of one group played the runners-up of another group from the same region, with the matchups determined by the group stage draw, and the group winners hosting the second leg.
!colspan=5|West Region
!colspan=5|East Region
West Region
Al-Ain won 6–2 on aggregate.----
Al-Ahli won 4–2 on aggregate.
----
Al-Hilal won 4–2 on aggregate.
----
Persepolis won 1–0 on aggregate.
East Region
Kawasaki Frontale won 7–2 on aggregate.----
2–2 on aggregate. Guangzhou Evergrande won on away goals.
----
Shanghai SIPG won 5–3 on aggregate.
----
Urawa Red Diamonds won 3–2 on aggregate.
Quarter-finals
The draw for the quarter-finals was held on 6 June 2017. In the quarter-finals, the four teams from the West Region played in two ties, and the four teams from the East Region played in two ties, with the matchups and order of legs decided by draw, without any seeding or country protection.
!colspan=5|West Region
!colspan=5|East Region
West Region
Al Hilal won 3–0 on aggregate.----
Persepolis won 5–3 on aggregate.
East Region
5–5 on aggregate. Shanghai SIPG won 5–4 on penalties.----
Urawa Red Diamonds won 5–4 on aggregate.
Semi-finals
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.
!colspan=5|West Region
!colspan=5|East Region
West Region
Al Hilal won 6–2 on aggregate.East Region
Urawa Red Diamonds won 2–1 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.
Urawa Red Diamonds won 2–1 on aggregate.