The mixed solutions of the hydrogenized element-NaOH-NaBH4 and HCI solution were fed into hydride vapor generator at the same rate by multi-flow peristaltic pump. Selenium element in the aqueous solution reacted on the nascent hydrogen to generate gaseous hydride. No separation was needed and the method was highly sensitive with little interference. The selenium content in spirulina was determined and a reliable analytical method was established. The determination limit of the method was 0.017 microg x g(-1), and the recovery of the samples was 98.89%-101.20%.