Phosphorus deficiency in infants may be asymptomatic at the initial stage, and then skeletal symptoms such as bone pain, neurological symptoms such as agitation and confusion, and anemia such as fatigue may occur. Phosphorus is an essential substance for bone development in infants, and if it is clearly deficient, it can lead to bone pain, rickets, or even pathologic fracture and other skeletal symptoms, as well as neurological symptoms such as agitation, sensory abnormalities, confusion, convulsions, coma, or even death. Due to the lack of phosphorus can cause the body’s lack of energy synthesis and the lack of 2,3-bisphosphoglycerate in the red blood cells, which can lead to generalized weakness, muscle weakness, hemorrhage and other symptoms, in addition to the gastrointestinal tract, oxygen deficiency can lead to lack of appetite, nausea, vomiting and so on. When infants have abnormal symptoms of phosphorus deficiency, they should be corrected in time under the guidance of a doctor.