The 26-year-old Ivory Coast international began his European club career with Standard Liege in 2009.
He then joined Anderlecht, for whom he scored seven goals in 47 league appearances, before moving on to Oostende in the summer of 2015.
"I am a striker, I am quick," he told the Fulham website.
The deal includes an option to buy Cyriac at the end of the season.
The Cottagers are 11th in the Championship, five points off the play-off places.
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Championship side Fulham have signed striker Gohi Cyriac on loan until the end of the season from Belgian Pro League side KV Oostende.