Embodiments relate to the field of wireless communication technologies and provide a method for performing channel sounding, a network-side device, and a terminal. A first terminal sends a resource scheduling request to a network-side device when the first terminal starts a communication connection with a second terminal. The resource scheduling request carrying information about the second terminal requests the network-side device to allocate a transmission resource for channel sounding between the first terminal and the second terminal. The first terminal receives a sounding reference signal sent by the second terminal, and obtains information of a channel for communication between the first terminal and the second terminal. The method enables quick and effective channel sounding between terminals, thereby increasing communication efficiency between the terminals.