A device-to-device (D2D) transmission distance obtaining method and a device, related to the field of communications technologies and applied to wireless communications, where the method includes obtaining, by a first device, transmit power information, where the transmit power information indicates a transmit power used by the first device for sending data to a second device, and sending, by the first device, the transmit power information to the second device such that the second device obtains a distance between the second device and the first device, where the distance between the second device and the first device is obtained according to the transmit power and receive power used by the second device for sending the data. Hence, a more accurate D2D distance can be obtained.