"Guess what??? I passed all my GCSE exams," the excited student wrote.
Brooklyn, 16, shared a black-and-white photo of himself posing with a celebratory piece of cake.
Brooklyn Beckham celebrated his exam results with a special dinner out
The teenager gave a slight smile to the camera while he held up his dessert of chocolate fondant and ice cream, accompanied with the word "Congratulations!" written out in chocolate sauce.
Brooklyn, who looked his cool and casual self in a checked shirt, received a flurry of messages from some of his four million Instagram followers.
"Congrats Brooklyn I bet your parents are really proud of you x," wrote one fan, while another simply commented, "Congratulations sweetie xx".
The budding photographer has been sharing artsy photos of his family including little sister Harper
Brooklyn is currently in the US enjoying the summer holidays with his parents and his younger siblings, Romeo, Cruz and Harper. The Beckhams used to call California their home when David, 40, played for LA Galaxy.
Before they return to London to go back to school, Brooklyn has been spending his free time with his family and has been on babysitting duty looking after his four-year-old sister.
The budding photographer shared an artsy shot of Harper peeking out at the camera between her fingers, while Brooklyn stood in the background, partly blurred out. "I'm watching u," he captioned the close-up shot.
Brooklyn has been hanging out with Gordon Ramsay's son Jack
The popular teen has also been hanging out with his close friend Jack Ramsay, the son of celebrity chef Gordon Ramsay and his wife Tana.
Brooklyn and Jack have been embracing all things American, from watching a baseball game to picking up food from a drive thru. "In heaven with@jackramsay1999," he captioned one photo of Jack at a fast food joint.
Another photo showed the pair rolling around on what looked to be an Uber Board – a revolutionary skateboard popular with footballers including Luis Suarez, Mario Balotelli and Steven Gerrard.