A fluorescent analytical method for the detection of trace Fe2+ and Fe3+ in water was established using ellagic acid(EA) as fluorescent probe.The effects of common metal ions,methanol concentration and pH value of media on the quantitative detection of Fe2+ or Fe3+ were investigated in detail.Results illustrated that a good linear relationship between the flourescence quenching and the concentrations of Fe2+ and Fe3+ was obtained within the range of 0.08-1.1 μmol/L with the detection limits of 72 nmol/L and 63 nmol/L,respectively.Meanwhile,Fe2+ could be detected accurately without significant interference using 10 mmol/L ammonium tartrate to mask Fe3+.In addition,the Job's plot analysis showed that the coordination ratios for EA to Fe2+ or Fe3+ were 1∶3 and 1∶2,respectively.The established method was used in the detection of Fe2+ and Fe3+ in tap water and Zhujiang River water with average recoveries of 81.0%-116%.