Gabriele Guarino was born on 14 April 2004 in Molfetta, Italy. He joined Bari's academy in 2018 and later moved to Empoli, where he developed into a centre-back. After loan spells at Modena and Carrarese, he became a key figure in Empoli's defence.

At international level he played for Italy from U18 to U21, finishing runner-up at the 2022 Mediterranean Games and at the 2023 FIFA U-20 World Cup. He received his first call-up to a senior Italy training camp in May 2026. In August 2026 he joined Samsunspor from Empoli on a five-year contract running until 2031, and wears the number 34 shirt.