Newcastle took a huge step towards securing an Aviva Premiership play-off place as Gloucester lost for the first time at home in the league this season.
Falcons' 21-20 win saw them move up to third in the table and extend their advantage over fifth-placed Gloucester from two to four points with five league games remaining.
Ally Hogg and Micky Young scored tries for Newcastle, with Joel Hodgson kicking three penalties and a conversion.
Jason Woodward, David Halaifonua, Mark Atkinson and Lewis Ludlow scored Gloucester's tries but crucially all were unconverted.
Gloucester made a bad start when Ruan Ackermann dropped the kick-off to concede early pressure and allow Falcons to take an early lead when Hodgson kicked a fourth-minute penalty.
Hodgson was a late replacement for Toby Flood, the former England fly-half having withdrawn through illness.
Gloucester scored the first try of the game after 14 minutes when captain Will Heinz took the ball to the blindside after a ruck 20 metres out from the opposition line. Woodward was put in possession and appeared to be hemmed in but the full-back skilfully kicked ahead to collect and score.
It took less than five minutes for the visitors to respond with their first try. Young neatly gathered an up and under before evading some poor Gloucester defence to give Hogg an unopposed 22-metre run to the line.
Hodgson's conversion gave Falcons a 10-5 lead at the end of an evenly matched first quarter before Gloucester wing Halaifonua was sin-binned for a head-high challenge on Sinoti Sinoti.
Sinoti went off for a head injury assessment and Halaifonua received lengthy treatment before Hodgson was able to kick the resulting penalty.
Newcastle could easily have scored again when a poor kick from Billy Burns and a careless error from Charlie Sharples nearly gifted Vereniki Goneva a simple try.
Sinoti failed his assessment before Halaifonua was able to return from the sin-bin with no further damage to the scoreboard but Hodgson's third penalty gave his side a 16-5 interval lead.
Eight minutes after the restart, the hosts reduced the arrears with their best move of the match. Sustained handling and a well-timed pass from Woodward gave Halaifonua the opportunity to brush aside a weak tackle from Falcons full-back Simon Hammersley to score.
Newcastle soon nullified this try when, two minutes later, they secured a turnover for Young to dummy his way through the defence to touch down.
Falcons looked in control when they led 21-10 with less than 15 minutes remaining but the home pack were becoming increasingly dominant to batter the opposition line. The Newcastle defence had to crack and so it proved when Atkinson forced his way over.
With four minutes to go, replacement Ludlow finished off a driving line-out but Billy Twelvetrees' wide-angled conversion went astray and Falcons picked up a crucial victory.