The invention relates to a method for preparing 
iron phosphate from ferrophosphorus. The ferrophosphorus is used as a part or the whole of a 
phosphorus source and an 
iron source for preparing the 
iron phosphate. The 
phosphorus source or the 
iron source is supplemented according to a mol ratio of (0.8-1.2):1.0 between 
total phosphorus elements and total iron elements. The ferrophosphorus is roasted in a dry and 
oxygen-containing 
atmosphere. The 
iron phosphate product is obtained by means of dry or 
wet oxidation product reaction. The method adopts the ferrophosphorus as the 
raw material for preparing the iron 
phosphate, makes full use of elements in the ferrophosphorus and creates a novel preparing process of iron 
phosphate. In addition, as the reaction process can be used for weakening or eliminating the influence of 
impurity elements in the ferrophosphorus on the iron 
phosphate product, the method indirectly purifies the ferrophosphorus and eliminates the influence of the impurities in the ferrophosphorus and the problem of severe 
corrosion caused by the existence of water during the 
roasting of ferrophosphorus. The reaction process has relatively 
low demand on apparatuses. The preparing method has simple process, short production flow and low production cost, is clean and environment-friendly, realizes high 
resource utilization rate, low investment and good benefit and is suitable for large-scale, industrial, low-cost and clean preparation of iron phosphate.