A washing tank device for separating foreign material and recycling aggregates is provided to separate floating foreign materials by installing an overflow part and an inclined screen at the upper side of a water tank and to separate fine aggregates and sludge fine particles by a fine aggregate separating inclined screen. The washing tank device for separating foreign material and recycling aggregates is composed of an overflow part(15) and a floating material separating inclined screen(16) installed at the upper side of a water tank(10) and a discharge port(13) formed at the lower end and opened or closed by a regulating valve(31). Fine aggregates and sludge fine particles naturally fallen and discharged through the discharge port are separated and cleaned by a fine aggregate separating inclined screen(20) installed at the lower side of the discharge port.
