A power transmitting apparatus comprising: a power transmitting unit configured to wirelessly transmit power to a plurality of power receiving apparatuses (101, 102); a switching unit configured to switch an operation mode of the power transmitting apparatus, in a case where power is being transmitted to a first power receiving apparatus, between a power transmission mode in which power is transmitted by the power transmitting unit to the first power receiving apparatus in response to a signal from the first power receiving apparatus, and a detection mode in which power transmission is performed by setting an output power of the power transmitting unit to a smaller value than an output power in the power transmission mode so as to detect a second power receiving apparatus that is different from the first power receiving apparatus; and a detection unit configured to detect a quantity of electricity generated by the second power receiving apparatus coming in proximity to the power transmitting apparatus during power transmission performed by the power transmitting unit in accordance with the output power of the power transmitting unit, wherein a quantity of electricity detectable by the detection unit in the detection mode is smaller than a quantity of electricity detectable by the detection unit in the power transmission mode, and the power transmitting apparatus detects the second power receiving apparatus on the basis of the quantity of electricity detected by the detection unit and transmits power to the second power receiving apparatus in response to a signal from the second power receiving apparatus. a power transmitting unit configured to wirelessly transmit power to a plurality of power receiving apparatuses (101, 102); a switching unit configured to switch an operation mode of the power transmitting apparatus, in a case where power is being transmitted to a first power receiving apparatus, between a power transmission mode in which power is transmitted by the power transmitting unit to the first power receiving apparatus in response to a signal from the first power receiving apparatus, and a detection mode in which power transmission is performed by setting an output power of the power transmitting unit to a smaller value than an output power in the power transmission mode so as to detect a second power receiving apparatus that is different from the first power receiving apparatus; and a detection unit configured to detect a quantity of electricity generated by the second power receiving apparatus coming in proximity to the power transmitting apparatus during power transmission performed by the power transmitting unit in accordance with the output power of the power transmitting unit, wherein a quantity of electricity detectable by the detection unit in the detection mode is smaller than a quantity of electricity detectable by the detection unit in the power transmission mode, and the power transmitting apparatus detects the second power receiving apparatus on the basis of the quantity of electricity detected by the detection unit and transmits power to the second power receiving apparatus in response to a signal from the second power receiving apparatus.