The flame atomic absorption method was applied to determine aluminum in jellyfish. The optimum detecting conditions were determined through many experiments. It established a nitric oxide-acetylene flame atomic absorption method to detect aluminum content in jellyfish that a good linear relationship is obtained in concentration range and correlation coefficient r2=0.9996. There are no significant differences in results after jellyfish samples were digested by three pretreatment methods. The detection limit of this method is 3.5 mg/L, the relative standard deviations are less than 5%, and the recovery is in the range of 88.50~104.20%. The test shows that: both the precision and accuracy accord with the demands, so this instrument analytical method could apply to research on quantitative detection of aluminum in jellyfish.