Head coach Dave Rice made the announcement Friday, saying the junior Smith had provided great energy and leadership while with the team.
Smith averaged 10.9 rebounds per game during the 2013-14 season and 11.1 points. He had 16 double-doubles last season.
In a statement issued by the school, Smith said he had a great experience at UNLV and plans to finish his classes while preparing for the draft.
Smith originally came to UNLV as a transfer from Connecticut, where he was a member of the Huskies' 2011 NCAA championship team.