Abstract: A front cover for protecting a diaphragm of an earpiece is disclosed. A circular through hole is provided at the center of the front cover. A series of trapezoidal through holes surrounding the circular through hole are provided at fixed intervals encircling the circular through hole. The total area of the circular through hole and the trapezoidal through holes accounts for 40% to 55% of the area of the front cover. By verifying the effect of different shapes and different hole areas on a frequency response curve, and by designing a front cover according to the curvature and shape of a diaphragm and adjusting the hole areas to optimize the frequency response curve of an earpiece, the earpiece front cover enables expansion of the effective frequency bandwidth of an earpiece, smoothing out of the high frequency curve, and reducing acoustic peaks and valleys.