The forward spent the second half of last season in the Premier League, on loan at Newcastle United, but failed to score once during a disappointing four-month spell at St. James’ Park.Nonetheless, it had been rumoured that De Jong could join elder brother Siem in sealing a permanent switch to Tyneside this summer - but the 23-year-old has now joined PSV for a reported €5.5 million.
"I want to get back on the field and show my qualities," the striker told his new club’s official television channel.
"The talks with PSV were very positive and I'm looking forward to playing here."
The Swiss-born attacker has played seven times for World Cup semi-finalists Netherlands, scoring one goal.
However, he netted just eight times after joining Gladbach from Twente in 2012 for €15m.