The Senators did not name the player when releasing the news Tuesday night.
The team said in a statement that the player has had mild symptoms and is in isolation.
The statement added that the organization is in the process of notifying anyone who has had known close contact with the athlete and is working with team doctors and public health officials.
The Senators have asked all of their players to remain isolated and says its medical staff will be monitoring the health of the players.
The NHL suspended its season last Thursday because of the COVID-19 outbreak.