The 2018 OFC Champions League knockout stage was played from 7 April to 20 May 2018.
The eight teams in the knockout stage played on a single-elimination basis.
The bracket was determined as follows: The bracket was decided after the draw for the knockout stage (quarter-finals, semi-finals, and final) was held on 5 March 2018 at the OFC Headquarters in Auckland, New Zealand.
In the semi-finals, the four quarter-final winners played in two ties, with the matchups and order of legs decided by draw.
In the final, the two semi-final winners played each other, with the order of legs decided by draw.