A spectrophotometric method for the determination of phosphorus content in formula milk powder forinfants and young children was developed. Under optimized experimental condiitons, the proposed method was highly reproducible and accurate. The following standard curve was established: y = 0.0372x + 0.0039 (R2 = 0.9997). The average recovery of this method was 98.5% with a RSD of 0.39%. Milk powder samples randomly selected from 30 commercial batches showed different levels of phosphorus, depending on age group. Three age groups decreasing order of phosphorus content were: young child’ formula milk powder, older infant’s milk powder and young infant’s milk powder, which were (448 ± 56), (382 ± 59) mg/g and (250 ± 58) mg/g, respectively. Morevoer, samples from different manufactures and the same age group also revealed greatly varying levels of phosphorus.