The invention relates to a filtering layer material for removing halate in water. The filtering layer material is particle mixture formed by iron-silicon-carbon alloy powder, magnesium-aluminum alloy powder and particle active carbon or particle anthracite. After water containing excessive halate is enabled to pass through the filtering layer material with thickness of 20-50cm by the flow rate of 3-20m/h, the concentration of the halate in the water can be greatly reduced. The filtering layer material and the using method can be used to remove halate in water, are particularly suitable for water plants to treat above-standard disinfection by-products of micro halate, and have the advantages of high industrial practicability, simple technological operation, obvious effect, high treatment capacity, long service cycle, low price, no secondary pollution and the like.