Objective: The present study aims to investigate the possible protective effects of lavender flowers powder and oil alone to healthy rats and against azathioprine induced toxicity of immune in rats. Methods: Forty two male Sprague-Dawley rats in six groups (7 rats each) were divided to main groups: Normal control group: Basil diet (BD), Positive control group: BD + azathioprine (25mg/kg), and four subgroups :Subgroup1 :BD + lavender powder (200 mg/ kg/b.w/day) as experimental control group (pre-treated), Subgroup 2:BD + lavender oil (20 ml/kg/b.w/day) as experimental control group (pre-treated), Subgroup 3 : BD + lavender powder + azathioprine, Subgroup 4 :BD +  lavender oil (20 ml/kg/b.w/ day)+ azathioprine. Results: The results indicated that azathioprine intake showed significant decreases in serum alpha tumor necrosis factor (-α TNF), interleukin-6 (IL-6), immunoglobulin E (IgE). Furthermore, hepatic reduced glutathione and nitric oxide levels were diminished matched with a significant rise in the level of malondialdehyde. Administration of either lavender powder or oil alone and with treatment of oil to azathioprine-induced toxicity of immune rats produced potential role against damaging impact of azathioprine. Both powder and oil of lavender reduced oxidative stress, ameliorated most of changes in the hematological parameters, improved nitric oxide and immunoglobulin E production. Conclusion: These results of enhanced hematological parameters and promoted immune system by pre/or treatment with lavender powder and oil alone and against azathioprine induced toxicity of immune in rats which, activities probably related to their potent antioxidative activity which due to their higher content of total phenolic compounds.