A sanitary washing apparatus comprising: a body configured to be placed on a toilet bowl; a spray nozzle configured to spray washing water onto an inner surface of the toilet bowl; a spray nozzle driver configured to rotate an orientation of an outlet orifice of the spray nozzle; and a control unit configured to control at least an operation of the spray nozzle driver, the control unit having following mode: a rinse mode in which the washing water is sprayed from the spray nozzle; characterized by: a foam generator configured to generate washing foam; wherein the spray nozzle is further configured to spray the washing foam onto the inner surface of the toilet bowl; wherein the control unit has the following further mode: a rotary foam-spraying mode in which the washing foam is sprayed into the toilet bowl through the spray nozzle while the orientation of the outlet orifice of the spray nozzle is being rotated; wherein in the rinse mode the washing water passes through the foam generator and is then sprayed from the spray nozzle; and wherein the control unit is further configured to change the speed of the spray nozzle driver according to a rotation angle of the outlet orifice. a body configured to be placed on a toilet bowl; a spray nozzle configured to spray washing water onto an inner surface of the toilet bowl; a spray nozzle driver configured to rotate an orientation of an outlet orifice of the spray nozzle; and a control unit configured to control at least an operation of the spray nozzle driver, the control unit having following mode: a rinse mode in which the washing water is sprayed from the spray nozzle; characterized by: a foam generator configured to generate washing foam; wherein the spray nozzle is further configured to spray the washing foam onto the inner surface of the toilet bowl; wherein the control unit has the following further mode: a rotary foam-spraying mode in which the washing foam is sprayed into the toilet bowl through the spray nozzle while the orientation of the outlet orifice of the spray nozzle is being rotated; wherein in the rinse mode the washing water passes through the foam generator and is then sprayed from the spray nozzle; and wherein the control unit is further configured to change the speed of the spray nozzle driver according to a rotation angle of the outlet orifice. a foam generator configured to generate washing foam; wherein the spray nozzle is further configured to spray the washing foam onto the inner surface of the toilet bowl; wherein the control unit has the following further mode: a rotary foam-spraying mode in which the washing foam is sprayed into the toilet bowl through the spray nozzle while the orientation of the outlet orifice of the spray nozzle is being rotated; wherein in the rinse mode the washing water passes through the foam generator and is then sprayed from the spray nozzle; and wherein the control unit is further configured to change the speed of the spray nozzle driver according to a rotation angle of the outlet orifice. a rotary foam-spraying mode in which the washing foam is sprayed into the toilet bowl through the spray nozzle while the orientation of the outlet orifice of the spray nozzle is being rotated; wherein in the rinse mode the washing water passes through the foam generator and is then sprayed from the spray nozzle; and wherein the control unit is further configured to change the speed of the spray nozzle driver according to a rotation angle of the outlet orifice.