Hull boss Steve Bruce has sanctioned the loan move for Oxley after bringing in former Rangers goalkeeper Allan McGregor from Besiktas.
Bruce is keen to send Oxley out on loan so that he can get some valuable first-team action under his belt.
A number of clubs are thought to have enquired about taking Oxley on loan, but Oldham have won the race for his signature.
Oldham boss Lee Johnson is in need of goalkeeping reinforcements after seeing Dean Bouzanis and Alex Cisak leave the club this summer.
Oxley is set to sign a six-month loan at Oldham with Hull having a 24-hour recall clause in the deal.