Abstract: Pallet shelf system (4) having at least two pallet decks, said system comprising at least two standard pallets (10a, 10b), each standard pallet comprising at least two fork pockets for receiving the forks of a forklift, at least four upright support posts (42a, 42b, 42c, 42d), two lower pallet base units (21a, 21b) comprising respective protrusions matching a respective fork pocket on a lower pallet (10a), and at least two upper pallet base units (41a, 41b), wherein two support frames (40a, 40b) are formed from said pallet base units and said upright support posts, said upper pallet base units (41a, 41b) supporting the upper pallet's outer pallet legs.