Goals from local heroes Sean Longstaff and Dan Burn - along with Miguel Almiron and Fabian Schar - helped down the Ligue 1 champions at St James' Park.
It is the Magpies' first win in the European Cup since the 2002/03 season to boost their chances of advancing into the knockout stages.
Incredibly, the Toon now sit top of Group F after two matches with four points following their 0-0 draw away at AC Milan a fortnight ago.
PSG went into Wednesday night's clash as the favourites as they looked to make it back-to-back group wins after beating Borussia Dortmund 2-0.
But they were reduced to scraps against a fired up Newcastle, who outworked and outclassed their French opponents.
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Kylian Mbappe baulked at a move to Tyneside during Euro 2020 as he joked that the weather wasn't warm enough for him.
And he was given a cold reception by the Newcastle faithful, as he was booed throughout the first half with the 2018 World Cup winner failing to have a sniff on goal.
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