The 2018–19 Horizon League men's basketball season began with practices in October 2018, followed by the start of the 2018–19 NCAA Division I men's basketball season in November.

Conference play began in January 2019 and concluded in February 2019.

Source[1] () first place votes Source[1] Preseason Player of the Year: Drew McDonald, Northern Kentucky This table summarizes the head-to-head results between teams in conference play.

On March 26, 2018, Detroit Mercy fired head coach Bacari Alexander after two seasons.

[2] On June 5, the school hired Texas Southern head coach Mike Davis as the Titans' new coach.