The invention aims at providing a bulk material cooler particularly for hot cement clinker, wherein the conveyance performance and the efficiency of the cooler are enhanced and problems due to wear are reduced. According to the invention, the cooling grates of several adjacent, elongated bottom elements extending in longitudinal direction of the cooler are put together, said bottom elements being movably controlled independently of one another between a work clearance stroke position in the direction of conveyance of the material to be cooled and a return stroke position in such a way that the material to be cooled is gradually conveyed through the cooler according to the walking floor transport system, wherein the bottom elements are configured as hollow bodies and enable the cold air to go through yet prevent grate sifting of the material to be cooled.