The invention relates to an ecological acoustic barrier capable of storing water and supplying water sustainably, the barrier is composed of multiple trapezoid box bodies of different dimensions, wherein the box bodies are assembled in the vertical direction to form a multilayer structure, and the box bodies are spliced in the horizontal direction to form an integral barrier; each trapezoid box body is of a trapezoid structure, a cavity water tank is arranged inside each trapezoid box body, multiple locating connecting columns are arranged on the upper base surface, multiple locating connecting holes are formed in the lower base surface correspondingly, a connecting groove is formed in the left side face, a connecting protruding column is arranged on the right side face correspondingly, water inlets are formed in the inclined face at one end, the water inlets are communicated with the cavity water tank inside the trapezoid box body, a planting slot is connected with the inclined face at the other end, a reserved water supply pipe is connected between the planting slot and the cavity water tank, overflow holes are formed in the upper portion of the cavity water tank, and each trapezoid box body is provided with circular holes which penetrate through the trapezoid box body vertically. By means of the barrier, water can be stored and supplied for a long time, so that the normal growth of sound barrier plants is facilitated, and meanwhile the ecological acoustic barrier is capable of purifying air and beautifying environment, simple in structure, easy to construct and maintain, convenient to apply in large scale, low in price and remarkable in greening effect.