The 2018 Horizon League women's basketball tournament (also known as Motor City Madness) was the conference tournament that ended the 2017–18 season of the Horizon League.
Regular-season champion Green Bay won the tournament and earned the Horizon League's automatic berth into the 2018 NCAA women's tournament.
The top six teams received a bye into the Second round.
This was a change from the previous season where the top two seeds received double byes into the Semifinals.
[1] Teams were seeded by record within the conference, with a tiebreaker system to seed teams with identical conference records.