A goal from striker Adam Idah on the hour-mark was enough for Jim Crawford's side to win their second match at the Pinatar Arena in the space of five days.
It is the second goal the Cork striker has scored against the Netherlands in just over a month. He was also on target in the UEFA Under-19 Championship Qualifying Round win between the sides in Longford in October.
Speaking after the win, Crawford said the trip to Spain, that also included a win against Belgium has been hugely productive for the side.
"The performances this week will cause Under-19 Head Coach Tom Mohan some headaches. A lot of the players performed to a very high standard.
"Those performances will probably affect our side in March, as a lot of the players will be with the Under-19s for the Elite Round. I'm delighted for them. We want to be pushing on our best players."
Republic of Ireland: Sean Bohan; Ray O'Sullivan, Tom Gaston, Kameron Ledwidge, Reece Staunton; Jason Knight (capt), Luca Connell (Brian McManus 70); Callum Thompson (Tyriek Wright 46), Sean Brennan (Barry Coffey 46), Shane Flynn (Conor Grant 82); Adam Idah.
Netherlands: Joey Kesting, Liam Van Gelderen, Omar Rekik, Nordin Musampa (capt), Quinten Timber, Crysencio Summerville, Damian Timan, Joshua Zirkzee, Immanuel Pherai, Marouan Azarkan, Enric Llansana.
Referee: Jose Joaquin Gallego Gambin