Deslauriers, 23, had one goal and 18 penalty minutes in 17 games for the Sabres this season, making his NHL debut after he was acquired from the Los Angeles Kings on March 5.
"Nick was able to step in and compete in every situation we put him in," Sabres general manager Tim Murray said. "We're confident that he will be an important part of our organization going forward."
Prior to being acquired by the Sabres, Deslauriers led the Manchester Monarchs, the American Hockey League affiliate of the Kings, in goals (18) and shots (217). He finished the AHL season with 19 goals and 42 points in 65 games in his first professional season as a forward, and added one goal and one assist in five Calder Cup playoff games with the Rochester Americans.