The invention belongs to the technical field of waste battery material recovery, and specifically discloses a method for recycling a positive active material of a waste lithium iron phosphate battery.The method comprises the steps of enabling the waste lithium iron phosphate battery to be subjected to short-circuit discharge and disassembly to obtain a material containing a positive plate, then carrying out crushing, binder removing and screening on the material to obtain the positive electrode active material; performing acid liquor curing defluorination treatment on the obtained positive electrode active material, wherein the curing process is carried out under a negative pressure condition or under continuous airflow purging; leaching the cured material with water to obtain a leachingsolution; and regulating the molar ratio of P, Fe and Li in the obtained leaching solution, and recovering to obtain lithium iron phosphate. According to the invention, the electrical properties of the recycled positive electrode active material can be obviously improved by carrying out the curing defluorination process on the waste positive electrode active material; for example, the discharge capacity is obviously improved, and the cycle performance is also improved.