O'Reilly joins the Boston Bruins' Patrice Bergeron and the Vegas Golden Knights' Mark Stone as finalists for the award.
The Selke Trophy winner is selected with votes from members of the Professional Hockey Writers' Association and will be revealed at the 2019 NHL Awards on June 19 in Las Vegas.
In the 2018-19 regular season, O'Reilly set career-highs in assists (49), points (77) and plus/minus (plus-22). He finished the season as the League's top face-off man, winning 1,086 draws. In January, O'Reilly represented the St. Louis Blues at the 2019 NHL All-Star Game - his second appearance at the mid-season showcase.