The invention discloses a sand-mould casting system, which comprises an iron type sand die and the like, wherein the iron mould sand die is combined by an upper die and a lower die to form a die cavity; an upper wall and a lower wall are respectively provided with a through hole communicated with the die cavity; a combined rail comprises a casting light rail, a die-compounding light rail and two parallel lateral light rails, wherein the casting light rail and the die-compounding light rail are in parallel; the two lateral light rails are respectively and vertically connected to two ends of the casting light rail and the die-compounding light rail; one side of the casting light rail is provided with a weighing and casting device; the iron mould sand die subjected to die compounding is arranged on the die-compounding light rail and enters the casting light rail after successively passing through the die-compounding light rail and one lateral light rail; the top of the through hole in the upper wall of the iron mould sand die just faces to the casting hole of the weighing and casting device; the casted iron mould sand die enters a die-splitting turnover device to separate the upper die from the lower die; one side of the die-splitting turnover device is provided with a die turnover ejection device used for ejecting out a workpiece in the die; then, the upper die and the lower die successively pass through a sand falling and vibrating device, a temperature control and sand ejecting and molding device and a turnover die-compounding device; and the turnover die-compounding device is positioned on one side of the die-compounding light rail.