The invention relates to a spent fuel storage pool, wherein an internal space formed by a peripheral wall (1) is divided into a fuel conveying channel (5) and an internal compartment by a first internal transitional compartment wall (3) and a first internal storage compartment wall (2) connected with the first internal transitional compartment wall (3), the internal compartment is divided into an internal transitional compartment (6) and an internal storage compartment by a second internal transitional compartment wall (3') equal in height with the first internal transitional compartment wall (3), one end of the second internal transitional compartment wall (3') is connected with the first internal transitional compartment wall (3), and the other end is connected with the peripheral wall (1); the upper edge elevation of the peripheral wall (1) is higher than the upper edge elevations of the first and second internal transitional compartment walls (3, 3'), and the upper edge elevations of the first and second internal transitional compartment walls (3, 3') are higher than the upper edge elevations of the first internal storage compartment wall (2). By adopting the structure, the intrinsic safety of the spent fuel storage pool is improved, and a matched process system is greatly simplified.