The invention discloses a device and a method for measuring and calibrating the sound intensity. The device for measuring and calibrating the sound intensity comprises a shell upper cover, a shell, a sleeve, a circuit board, a loudspeaker, a coupling cavity, a coupling element, a coupling cavity bottom cover, and a reference microphone. The device for measuring and calibrating the sound intensity acquires a calibration signal generated by an external device and can be applied in various types of sound intensity measuring and calibrating environments and methods. Meanwhile, through the conduction of the sleeve and the conduction of the shell, a stable and effective sound source is obtained in the coupling cavity. Meanwhile, based on the coupling element of a symmetrical structure, a reference signal and a measurement signal, that are completely consistent with each other, can be obtained. Through comparing a reference signal fed back from the reference microphone and the above signal of the circuit, the calibration signal is more stable and more accurate. At the same time, the device for measuring and calibrating the sound intensity is highly integrated, convenient to carry about and immediate in detection.