Abstract: Spirulina maxima was cultured in the media containing NaC1 concentration from 0.1% to 5.0%. It was obviously found that the growth of the algae was inhibited when NaC1 concentration was higher than 2.0%. Superoxide dismutase (SOD), ascorbate peroxidase (ASA-POD), catalase (CAT) and the content of MDA were determined after 7 days. The result showed that the activity of SOD increased under slat stress; the activity of ASA-POD and CAT increased under low stress,while the activity of ASA-POD decreased quickly and CAT was lost under higher stress; At first the content of MDA decreased when the salt stress was increasing,but then it came back to the level of the control with the increasment of the salt stress.