Salem’s contract was due to expire at the end of 2019 prior to signing the two-year extension.
Salem told Melbourne Media he was pleased with the deal.
“It got done pretty quickly,” he said.
“I probably wasn’t too fussed about it, as I knew it was going to happen eventually – it was just a matter of when.
“But it was good to get it done before the season.”
Since making his debut in 2014, Salem has played 70 games for the Demons and Melbourne general manager of football operations Josh Mahoney said the club was delighted to extend Salem.
“We’ve been really impressed by his development, particularly over the past few years,” Mahoney said.
“He gives us a lot of variety with the positions he can play… and he’s entering a good stage of his career where his best is well ahead of him.”
Salem and the Demons will begin the 2019 home and away season with a Saturday afternoon matchup with the Power on 23rd March.