The embodiment of the invention is suitable for the technical field of mining, and provides a method and device for determining the volume of a tailings disposal goaf and computer equipment, the method comprises the steps that the amount of tailings to be disposed is determined, and the amount of the tailings to be disposed is equal to the amount of tailings left after a first goaf generated by a first ore body is disposed; based on the amount of the tailings to be treated, determining a relational expression between the volume of a second ore body to be mined and the amount of the tailings which can be treated; determining a stack density formula; and according to the relational expression between the volume of the second ore body and the amount of the tailings capable of being disposed and the pile density formula, calculating the volume of a goaf required by the amount of the tailings to be disposed. By adopting the method, the volume of the goaf required for treating the tailings can be accurately determined.