Floyd K. Whittemore (October 2, 1844 – March 4, 1907) was an American politician and businessman.
Born in Auburn, New York, Whittemore and his family moved to Sycamore, Illinois, in 1848.
Whittemore worked for the DeKalb County, Illinois, circuit clerk office.
He worked as the cashier for the State National Bank of Springfield.
From 1899 to 1901, Whittemore served as Illinois state treasurer and was a Republican.