Fiji are looking for a new coach just 18 months before the Rugby World Cup after parting ways "by mutual agreement" with Mick Byrne on Wednesday.
Fiji Rugby said Australian Byrne would "step down from his role, effective immediately".
Byrne had been in charge of the national team since 2024 after a stint at the helm of Super Rugby side Fijian Drua, but appears to have had a difference of opinion with the management over future plans.
"Mick has been fully committed to his role and remains dedicated to the players and staff," said Fiji Rugby CEO, Koli Sewabu.
"Out of respect for the team and to ensure the programme can continue to the new direction that Fiji Rugby has set for the future, Mick and Fiji Rugby have agreed to part ways."
Fiji's next test assignments are in Europe in July, where they will face Wales, England and Scotland on consecutive weekends in the Nations Championship.
During Byrne's tenure as coach, Fiji enjoyed wins over Scotland, Wales and Japan.
"It has been an honour to work with the Flying Fijians players and staff," said Byrne. "And before that the Drua players and staff.
"I have been overwhelmed by the support of 'the world's best' Fiji fans during my five-year involvement – their warmth and welcome have meant a great deal to me.
"I remain fully committed to the game and wish Fiji Rugby every success moving forward."