The winger, who arrived on loan from Manchester United on Thursday, struck in injury time to hand Palace their first point of the new season
Dwight Gayle’s goal inside the opening minute handed Neil Warnock the perfect start to his second stint in charge at Palace but Newcastle were level before the break through Daryl Janmaat’s effort.
Jason Puncheon put Palace back in front three minutes after half-time but 18-year-old midfielder Rolando Aarons pulled Alan Pardew’s men level.
|VIEW FROM ST JAMES' PARK
|By Harry Slavin
Welcome back to the Premier League Neil Warnock. His Palace side today displayed the type of never-say-die attitude you’d expect from one of his teams and it’s fitting his side clawed their way back from adversity to claim a point on Tyneside.
It could have been so different had the Eagles been able to consolidate either lead produced by Gayle or Puncheon, but the arrival of Aarons from the Newcastle bench turned the game on its head.
From Pardew’s point of view, a stoppage-time equaliser will be tough to stomach, but even he would be hard pushed to begrudge Warnock this deserved point on his return.
Mike Williamson looked to have secured three points for Newcastle with his goal two minutes before injury time but Zaha, who completed his loan move from Manchester United earlier this week, netted late on to secure Palace’s first point of the new season.
Palace began with confidence and scored after just 30 seconds when Gayle slotted past a stranded Tim Krul from point-blank range after the Dutch goalkeeper had done well to tip Marouane Chamakh's effort on to his left-hand post.
Newcastle failed to mount a response after that early setback and instead it was Palace that came close to adding a second, Puncheon lashing over the bar at the near post after more good build-up play from the visitors.
The hosts did slowly begin to mount pressure as they dominated possession, and Pardew's side found the leveller eight minutes before half-time when Janmaat scuffed beyond Palace goalkeeper Julian Speroni after seeing his initial effort blocked.
Palace replicated their fast start to the first half in the second, with Puncheon - named in Warnock's starting side despite the pair having a public spat earlier in the year - proving his worth in spectacular fashion.
The winger was afforded the time to control the ball in the area by the Newcastle defence and unleashed an acrobatic volley into the bottom corner.
Yoan Gouffran was then denied a leveller by Speroni before Zaha - brought on for the injured Gayle - was thwarted by Krul.
Substitute Aarons headed in to equalise with 17 minutes remaining after Palace had failed to clear Remy Cabella's corner, and the game looked set to end in heartbreak for Palace when Williamson scored in the 88th minute.
But Zaha, who had already had one goal disallowed for offside, had the final say as he capitalised on sloppy Newcastle defending.