Abstract: It is known that spirulina is rich from the point of view of vitamin, mineral, essential fatty acids and antioxidants such as caretinoids. In this study, the changes on oxidant and antioxidant system occured by spirulina and protective effect of spirulina against lipid peroxidation in lead toxication in rats are examined. Forty adult female wistar albino rats were divided into four experimental groups: control, spirulina, lead and spirulina + lead-treated. At the end of the experimental period (1 month), animals in all four groups were fasted for 12 h and blood samples were taken for the determination malondialdehyde (MDA), reduced glutathione (GSH), ascorbic acid, nitrate and nitrite levels. There was a statistically significant difference between the groups for all parameters except for serum ascorbic acid. It is determined that there was a crucial increase in the level of GSH belonging to spirulina treated group when compared with control group, lead treated group and spirulina + lead treated group (p<0,05). It was observed that the lecvel of MDA which is an important sign of lipid peroxidation for lead treated group is statistically crucial when compared with control group and spirulina treated group when compared with the other groups and this increase is statistically important (p<0.05). Morover, it is seen that there is an increase in the level of nitrate and nitrite for spirulina treated group when compared with the other groups and this increase is statistically important (p<0.05). Consequently, it is indicated that lipid peroxidation occured an animals treated by lead is prevented by the future of antioxidant of spirulina platensis and therefore it assists the level of antioxidants in circulation.