Louis van Gaal's men have been far from impressive in their build-up to the tournament and looked below par once again in Amsterdam against their Welsh visitors, who were without star names including Gareth Bale and Aaron Ramsey.
Arjen Robben scored the opening goal of the encounter shortly after the half-hour mark, but chances were few and far between throughout.
There was, however, one more goal for the home side to celebrate, when Jeremain Lens found the net from a Robben cross in the 76th minute.
Van Gaal brought Leroy Fer in for the injured Jonathan de Guzman in his only change of personnel from the 1-0 win over Ghana on Saturday, while there was a debut for defender James Chester in a Welsh defence that was missing captain Ashley Williams.
And Chris Coleman's charges had to be on high alert in the early stages as Robin van Persie – celebrating the ninth anniversary of his international debut - had the first chance of the encounter, but Wayne Hennessey got down well to deny his low drive from just inside the penalty area.
Robben dragged an effort wide of the right-hand post in the ninth minute, before Wales settled and began to put the hosts under pressure at the back – Van Gaal's men far from assured in defence.
However, just as Netherlands' sluggish start was beginning to draw the ire of the home crowd, Robben burst into the penalty area only to see his strike deflected over by Chris Gunter.
And it was Robben who eventually made the breakthrough, netting in the 32nd minute after a Van Persie shot had ricocheted out off the shin of Hennessey.
Van Persie diverted agonisingly wide of the left-hand upright five minutes before the break as the hosts were made to settle for a one-goal advantage at the interval.
The first 20 minutes of the second period passed without incident, but Wales almost caught the Oranje napping when substitute Jermaine Easter latched onto a Gunter throw-in, but his close-range effort was kept out by Jasper Cillessen.
Fulham's George Williams came off the bench to make his Wales debut and the home side had Ron Vlaar to thank for denying the youngster an almost instant goal to go with it.
But it was the hosts who had the final say, as Robben – arguably his side's brightest player in these pre-tournament friendlies – found an unmarked Lens with a cross from the right, and the Dynamo Kiev man tapped home unmarked.
It may have been another win for the Dutch, but Van Gaal will be well aware his squad will need to up their game for their World Cup curtain-raiser against defending champions Spain a week on Friday.