Following the arrest of a 34-year-old woman and a 50-year-old man last week, a 56-year-old woman has now been arrested.
A Police statement said: "Fraud squad detectives have arrested a third person this morning in connection with an inquiry into the financial affairs of Hull City Association Football Club Ltd.
"A 56-year-old woman from Kirk Ella, East Yorkshire is being questioned at a police station in Hull."
The pair that were arrested last week are out on bail until April.