The 27-year-old Liverpool centre-back is the first defender to win the award since Manchester City's Vincent Kompany did so in 2011/2012, having played in all of Liverpool's 37 league matches ahead of its final-day clash with Wolverhampton Wanderers.
Across those 37 appearances, Van Dijk was part of a defence that kept 20 clean sheets and collected 29 victories, and the award comes after he was named the PFA Players' Player of the Year in April.
"It's a great honour and I'm very proud," Van Dijk said.
"Without everyone here at Liverpool, fans and players, it wouldn't be possible so I will definitely give them credit for all of it as well.
"I think the whole season in the Premier League has been outstanding."
Van Dijk succeeds Liverpool team-mate Mohamed Salah as the winner of the award, having seen off competition from the Egyptian, Sadio Mane, Sergio Aguero, Bernardo Silva, Raheem Sterling and Eden Hazard.