The invention is suitable for the technical field of ecological restoration, and provides a method and device for determining an underground tailing filling strategy and terminal equipment, and the method comprises the steps that treatment demand parameters of fine sand grade tailings are obtained; inputting the disposal demand parameters into a filling strategy prediction model for processing, and outputting a filling strategy of the fine sand tailings; wherein the filling strategy of the fine-sand-grade tailings comprises the lime-sand ratio of the fine-sand-grade tailings, the lime-sand ratio meeting the disposal requirement is output according to the disposal requirement of the fine-sand-grade tailings by constructing a filling strategy prediction model, and the appropriate filling strategy can be determined for the fine-sand-grade tailings.