Methomyl (MET) is a widely used pesticide that has a number of health harmful impacts. Many bioactive and antioxidants components found in spirulina (SP). The target of this study was to estimate the ameliorative role of SP on MET-induced biochemical and histological alterations in rat's kidneys. Rats were divided into four groups; group I employed as a control group, group II was SP-treated rats that received SP orally (500 mg/kg b.wt) for three weeks, group III was MET-treated rats that received MET orally (1/20 of LD50) for three weeks and group IV was rats that received both MET and SP for three weeks with the same previous doses. After three weeks, rats of all groups were weighted and sacrificed. Sera samples were used for biochemical analysis of urea, creatinine and uric acid concentrations and kidney tissues were used for malondialdehyde (MDA), interlekine-6 (IL-6), glutathione (GSH) concentrations and catalase (CAT) activity estimations, besides histological examination and immunohistochemical investigation of tumor necrosis factor-α (TNF-α). The present study results summarized that MET induced renal impairment and co-treatment of SP and MET caused significant reduction in urea, creatinine, uric acid, MDA, IL-6 concentrations, significant elevation in GSH concentration and CAT activity and lessened histological and immunohistochemical alterations owing to SP high content of antioxidant and free radicals scavenging capacity.