The Galician club have three wins from 12 matches and lost 4-2 at home to European champions Real Madrid on Sunday under Argentine Mohamed who replaced Juan Carlos Unzue in May.
Cardoso left Nantes at the start of October after four months at the Ligue 1 club following an impressive campaign at Rio Ave in his native Portugal last season.
He had previously worked as an assistant coach at Deportivo La Coruna, Celta's local rivals, between 2012-13.
"(He) had a splendid season in charge of Rio Ave, taking them to their best finish in the Portuguese league, qualifying them for the Europa League," Celta said in a statement.
(Reporting by Rik Sharma; editing by Ken Ferris)
