The alteration comes as a result of kit clashing, with none of the Magpies' three released jerseys being deemed suitable for the clash at the Amex Stadium.
Eddie Howe's side primarily play in their traditional black and white shirt, but also have a navy blue away shirt and a white and green third kit that draws a striking resemblance to the Saudi Arabian national kit.
As a result, Newcastle will be heading to the south coast wearing a turquoise shirt, with their traditional black shorts and black socks.
A statement on the club website read: "Newcastle United will wear a special one-off Castore shirt adorned with the Tyneside skyline during this week's Premier League trip to Brighton.
"The Premier League has ruled that the Magpies' three new 2022/23 Castore kits - black and white, navy blue and white respectively - will all clash too closely with Brighton's blue-and-white-striped home kit.
"Accordingly, Newcastle United has gained special dispensation from the Premier League to wear a sky-blue jersey that features the silhouette of St. James' Park and several city landmarks - including the world-famous Tyne Bridge - teamed with black shorts and socks.
"The shirt will ordinarily be worn as a warm-up shirt by the players on matchdays but will feature FUN88, noon.com and Premier League branding for the trip to the Amex Stadium."
Newcastle got their season off to a winning start as they beat Nottingham Forest in their opening fixture.
But they face a tough battle with Brighton going into the game off the back of beating Manchester United 2-1 at Old Trafford.