"It is sad, but it is their decision," said Serevi.
"I am without a job and I wish Fiji well in rugby."
The move comes after differences in opinion over selection policy, with Serevi reportedly unhappy with the make up of the team selected for the next two legs of the IRB World Sevens Series.
Serevi believed the four national selectors - Ilivasi Tabua, Vuata Narisia, Dan Lobendan and Mosese Taga - had made a mistake in choosing an inexperienced squad, particularly for the demanding Wellington Sevens in New Zealand.
Iliesa Tanivula, the coach of the Fijian Sevens reserve team and a former Auckland winger, replaces Serevi as national Sevens coach with immediate effect.