Leyton Orient Koroma made his first-team debut for
Leyton Orient on 9 April 2016 as a second-half
substitute in a 3–0 league defeat away to
Barnet. On 31 January 2020, Koroma joined
Rotherham United on a six-month loan deal.
2020–21 He scored his first goal for Huddersfield in a 2–1 win at
Swansea City on 17 October 2020. On the 8 December he scored for the third consecutive home game in the 2–0 home victory over
Sheffield Wednesday. In the same game he injured a hamstring and was out for over 4 months. He returned for the final four games of the season, in which he scored in the away 5–2 defeat to
Blackburn Rovers and 2–2 draw away to
Reading FC.
Portsmouth (loan) On 1 September 2022, Koroma joined
EFL League One side
Portsmouth on a season-long loan, reuniting him with
Danny Cowley, who managed him at Huddersfield. On 11 January 2023, Portsmouth opted to end Koroma's loan. Koroma was released by Huddersfield Town at the end of the
2024–25 season.
Leyton Orient Koroma returned to Leyton Orient on 16 July 2025, signing a three year contract. ==International career==