Despite a late West Ham fightback, goals from Ciaran Clark, Federico Fernandez and Jonjo Shelvey helped Newcastle to a deserved victory, ending a run of three consecutive away defeats for Steve Bruce's side.
Newcastle were impressive as they scored more than once for the first time this season, putting pressure on Manuel Pellegrini as West Ham's winless run extended to five games.
Story of the match
Newcastle made a very bright start to the game, Miguel Almiron and Allan Saint-Maximin both finding space and threatening the Hammers with intelligent movement off the ball.
The visitors were rewarded for their early endeavours and they took a deserved lead after 13 minutes, Clark heading past Roberto following a dangerous free-kick that was won by the lively Almiron.
West Ham struggled to create anything of significance throughout the opening stages and looked like conceding everytime the Magpies broke away on the counter-attack, Pablo Zabaleta and Aaron Cresswell both unable to deal with Newcastle’s speed in wide areas.
It came as no surprise that Steve Bruce’s side doubled their advantage soon after the 20-minute mark thanks to another headed goal, this time Fernandez glancing his effort into an empty net after Roberto failed to collect Jetro Willems’ floated cross.
The home side enjoyed some possession in the opposition half after going behind, however they should have found themselves 3-0 down midway through the first-half, Roberto with a crucial save to deny Saint-Maximin after the Frenchman raced clear through on goal.
The home crowd’s frustration was evident as Pellegrini’s team proved unable to break down a structured Newcastle outfit owing to a clear lack of energy, creativity and desire from the hosts.
It was then the visitors who came very close to grabbing a third, Saint-Maximin squandering another great chance that was identical to his earlier effort, and then the woodwork denying Shelvey a delightful long-range goal.
Martin Dubravka was eventually forced to make a couple of saves just before the interval, Sebastien Haller with an audacious overhead kick and Fabian Balbuena with a headed effort, but both attempts came to nothing and the Hammers were booed off by the home supporters.
Following a dismal first-half, West Ham made two changes after the break, Mark Noble making way for Manuel Lanzini and Albian Ajeti replacing Andriy Yarmolenko.
Despite Pellegrini's substitutions, Newcastle had the ball in the back of the net again moments after the restart, however, DeAndre Yedlin was adjudged to have converted from an offside position, and his goal was ruled out.
It didn't take long for the Magpies to score again though, Shelvey making it 3-0 with a curled free-kick minutes later, from which 'keeper Roberto should have done a lot better.
West Ham pushed forwards looking for an unlikely route back into the game, Lanzini providing some creativity in an otherwise uninspiring attack.
Another failed overhead kick from Haller, and a long-distance effort from Declan Rice that flew well over, summed up West Ham's awful afternoon.
The home side managed to grab a goal back with Balbuena tapping in from a corner on 73 minutes, igniting hopes of a remarkable comeback.
After a continued spell of slow, uninspiring attacks Robert Snodgrass made it 3-2 in the 90th minute with a guided strike from the edge of the area, sending the Hammers into injury time with a chance of grabbing a point.
However, the away side showed strength to hold on, a solid defensive display sending the Geordies home happy with three points.
Magpies move out of relegation zone
A well-deserved three points for Steve Bruce's side lifts them four points clear of safety.
The Magpies will be hoping to use the away victory as momentum, a home fixture against Bournemouth their next test.
In what is now proving a regular occurrence, Haller found himself completely isolated in the Hammers’ attack, starved of any service by those behind him.
Ajeti was introduced at half-time, providing the Frenchman with a much-needed partner in attack, however they were unable to help their side find a way back into the game.
Saint Maximin and Almiron impress
Saint-Maximin and Almiron had a field day at the London Stadium, causing untold problems for West Ham’s full-backs who were unable to deal with their pace and trickery.
Although neither managed to score, they both showed signs of promise in attack, and had their end-product been better, each of them could have ended up with a brace.