The present disclosure relates to an image forming apparatus including: a developing unit; a developer supply unit; a toner density detecting unit; a mode setting unit; a first supply control unit; a second supply control unit; and a second standard value setting unit. The toner density detecting unit detects toner density. The mode setting unit, when toner density detected by the toner density detecting unit is less than a first standard value and a second standard value that is lower than the first standard value or more, sets a first developer supply mode as a mode for supplying developer to the developing unit and when the toner density detected by the toner density detecting unit is less than the second standard value, sets a second developer supply mode as a mode for supplying developer to the developing unit.