OBJECTIVE： To establish a method for the determination of weight average molecular weight （Mw） and molecular weight distribution （D） of ferric carboxymaltose. METHODS： HPGPC method was adopted to detect the Mw and D of 3 batches of Ferric carboxymaltose injection （imported） and its raw material （self-made）. The determination was performed on TSK G4000 PWXL column with 0.1％ sodium azide solution with the flow rate of 0.5 ml/min. The detector was refractive index detector； the column temperature was set at 35 ℃， and sample size was 20 μl. The results were calculated with GPC software. RESULTS： RSDs of precision， stability and reproducibility tests were all lower than 3.0％ （n＝6）； Mw and D of 3 imported samples were 157 667 and 1.30； those of self-made samples were 162 000 and 1.42. CONCLUSIONS： The method has high precision， good stability， repeatability and durability. It can be used for the determination of Mw and D of ferric carboxymaltose.