The Andalusian club, who are three points above the relegation zone, issued a brief statement thanking the 52-year-old former Argentina international, who had only arrived in Seville last July.
"Matias Almeyda has been relieved of his duties as Sevilla FC first team head coach," the statement read.
"Sevilla FC want to thank Matias Almeyda and his team for his efforts and professionalism and wish him the best for the future."
The statement made no mention of a replacement or a potential interim coach, ahead of the upcoming two-week international break.
Almeyda, who began his coaching career at River Plate in 2011, managed AEK Athens from 2022 to 2025 before being appointed by Sevilla on a three-year contract.