A method for testing function of an adaptor, being applicable by a testing device and comprising: sending a test signal to the adaptor, wherein the test signal is a first test signal for causing the adaptor to launch a protection mechanism; detecting a first voltage, wherein the first voltage is outputted in a preset first duration by the adaptor according to the test signal; and determining a working state of the adaptor according to the first voltage comprises: detecting whether the first voltage is higher than a first threshold voltage; determining that the working state is that the protection mechanism of the adaptor fails, in response to the first voltage being higher than the first threshold voltage; and determining that the working state is that the protection mechanism of the adaptor is normal, in response to the first voltage being lower than or equal to the first threshold voltage; wherein, the first test signal is a first signal for instructing the adaptor to output a third voltage, and the third voltage is beyond a first voltage range in which the testing device can work safely; or the first test signal is a first communication instruction which the adaptor is unable to recognize; or the first test signal is a second communication instruction which the adaptor is able to recognize, wherein the second communication instruction is sent to the adaptor by the testing device according to a first timing which is a timing other than that specified by a communication protocol between the testing device and the adaptor; or the first test signal is indicative of an input alternating current voltage of the adaptor, wherein the input AC voltage is beyond a voltage range in which the adaptor can work safely. sending a test signal to the adaptor, wherein the test signal is a first test signal for causing the adaptor to launch a protection mechanism; detecting a first voltage, wherein the first voltage is outputted in a preset first duration by the adaptor according to the test signal; and determining a working state of the adaptor according to the first voltage comprises: detecting whether the first voltage is higher than a first threshold voltage; determining that the working state is that the protection mechanism of the adaptor fails, in response to the first voltage being higher than the first threshold voltage; and determining that the working state is that the protection mechanism of the adaptor is normal, in response to the first voltage being lower than or equal to the first threshold voltage; wherein, the first test signal is a first signal for instructing the adaptor to output a third voltage, and the third voltage is beyond a first voltage range in which the testing device can work safely; or the first test signal is a first communication instruction which the adaptor is unable to recognize; or the first test signal is a second communication instruction which the adaptor is able to recognize, wherein the second communication instruction is sent to the adaptor by the testing device according to a first timing which is a timing other than that specified by a communication protocol between the testing device and the adaptor; or the first test signal is indicative of an input alternating current voltage of the adaptor, wherein the input AC voltage is beyond a voltage range in which the adaptor can work safely. detecting whether the first voltage is higher than a first threshold voltage; determining that the working state is that the protection mechanism of the adaptor fails, in response to the first voltage being higher than the first threshold voltage; and determining that the working state is that the protection mechanism of the adaptor is normal, in response to the first voltage being lower than or equal to the first threshold voltage; wherein, the first test signal is a first signal for instructing the adaptor to output a third voltage, and the third voltage is beyond a first voltage range in which the testing device can work safely; or the first test signal is a first communication instruction which the adaptor is unable to recognize; or the first test signal is a second communication instruction which the adaptor is able to recognize, wherein the second communication instruction is sent to the adaptor by the testing device according to a first timing which is a timing other than that specified by a communication protocol between the testing device and the adaptor; or the first test signal is indicative of an input alternating current voltage of the adaptor, wherein the input AC voltage is beyond a voltage range in which the adaptor can work safely.