A power supply apparatus that wirelessly supplies power to an electronic device, comprising: communicating means (102, 104, 108) for contactlessly transmitting power and transmitting/receiving information; holding means for holding, when authentication is first performed with an electronic device via the communicating means (102, 104, 108), information indicating a communication mode when communication is established with the electronic device; and controlling means for controlling the communicating means (102, 104, 108) so as to perform communication in a communication mode based on the information held in the holding means, when a second authentication is performed with the electronic device via the communicating means (102, 104, 108), wherein the controlling means includes: determining means for, when a first authentication is performed with an electronic device, establishing communication with the electronic device by outputting power at a pre-set first level via the communicating means (102, 104, 108), and determining whether or not the electronic device includes a rechargeable battery; and transitioning means for, when the determining means has determined that the electronic device includes a rechargeable battery, transitioning to second authentication for charging the battery of the electronic device, and the communicating means (102, 104, 108) is NFC, Near Field Communication, communicating means, wherein when the transitioning means causes second authentication to be performed with the electronic device, the controlling means is configured to not reply to a carrier signal transmitted by the electronic device as an initiator, during a period before a time determined in the first authentication with the electronic device has elapsed. communicating means (102, 104, 108) for contactlessly transmitting power and transmitting/receiving information; holding means for holding, when authentication is first performed with an electronic device via the communicating means (102, 104, 108), information indicating a communication mode when communication is established with the electronic device; and controlling means for controlling the communicating means (102, 104, 108) so as to perform communication in a communication mode based on the information held in the holding means, when a second authentication is performed with the electronic device via the communicating means (102, 104, 108), wherein the controlling means includes: determining means for, when a first authentication is performed with an electronic device, establishing communication with the electronic device by outputting power at a pre-set first level via the communicating means (102, 104, 108), and determining whether or not the electronic device includes a rechargeable battery; and transitioning means for, when the determining means has determined that the electronic device includes a rechargeable battery, transitioning to second authentication for charging the battery of the electronic device, and determining means for, when a first authentication is performed with an electronic device, establishing communication with the electronic device by outputting power at a pre-set first level via the communicating means (102, 104, 108), and determining whether or not the electronic device includes a rechargeable battery; and transitioning means for, when the determining means has determined that the electronic device includes a rechargeable battery, transitioning to second authentication for charging the battery of the electronic device, and the communicating means (102, 104, 108) is NFC, Near Field Communication, communicating means, wherein when the transitioning means causes second authentication to be performed with the electronic device, the controlling means is configured to not reply to a carrier signal transmitted by the electronic device as an initiator, during a period before a time determined in the first authentication with the electronic device has elapsed.