The news comes just one week before Oldham are due to play Sunderland in the next round of the Papa John’s Trophy at the Stadium of Light.
Oldham are currently 22nd in League Two after a poor start to the season which has seen Curle win just four of 18 in the fourth tier.
A statement on the club’s website read: “We would like to thank Keith for his efforts during his time at Boundary Park and would also like to wish him well for the future. His assistant Colin West has also been relieved of his duties.
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“Selim Benachour will step up from the Academy and take over as Interim Head Coach for the time being with the club making no further comment now as the team continues its preparations for the game at the weekend.”
Lee Johnson’s Sunderland are set to face Oldham on Wednesday, December 1.