In recent years, attention has been developed to the protective biochemical function of natural antioxidants contained in dietary plants. Plant medicines are generally perceived as safe products and the toxicity of these plants has not been reported. Nuts are high in natural antioxidants and other nutrients that may improve glucose homeostasis and support the antioxidant system. In diabetes, the diet must provide the right amount of nutrients and calories in order for the individual to reach and maintain the ideal weight, stabilize the blood glucose levels close to the norm. The objective of this study was to elucidate the hypoglycemic and antioxidative activities of pistachio nuts which are consumed widely in Anatolia, Turkey. Diabetes was induced in rats by intraperitoneal injection of a single dose of 45 mg/kg STZ freshly dissolved in citrate buffer. Plasma and serum samples were used to determine total antioxidant activity (TAA), superoxide dismutase (SOD) activity, reduced glutathione, protein sulfhydryls, malondialdehyde (MDA) and sialic acid levels. According to our results, pistachio consumption caused a significant reduction in MDA levels (P<0.001) and an increase in TAA (P<0.01) in pistachio treated diabetic rats. Furthermore, in pistachio treated control group, we found an insignificant decrease (P>0.05) in glucose levels. The results indicate that pistachio consumption can provide antioxidant protection to membrane lipids, support the antioxidant system and inclusion of pistachios in a healthy diet beneficially affects diabetic risk factors in a dose-dependent manner.