Background: Aspartame (ASP) is a widely used artificial sweetener. Aspartame-containing foodstuff and drinks are usually consumed by diabetic patients and for weight loss. Kiwi fruits have antioxidant and anti-inflammatory actions. Objective: The aim of the present study was to evaluate the effect of aspartame and the possible role of kiwi fruit on the structure of the lung in adult male albino rats. Materials and Methods: Forty adult male albino rats were used in three groups; Group I served as control, Group II received aspartame orally in a dose of 40 mg/kg dissolved in distilled water daily for six weeks, Group III received kiwi fruit extract orally in a dose of 37 g/kg body weight three times weekly together with aspartame 40 mg/kg for six weeks. Body weight, serum tumor necrosis factor-α (TNF-α) and nitric oxide (NO) and tissue malondialdehyde (MDA) and superoxide dismutase (SOD) were measured. Lungs were dissected out for staining with H&E, Masson trichrome, alpha-smooth muscle actin (α- SMA), and caspase 3. Results: Aspartame caused elevated level of serum TNF-α and NO and tissue MDA and SOD and significant histopathological alterations in the lung tissue. Aspartame and Kiwi group showed relatively normal levels of TNF-α, NO, MDA, and SOD and less alteration in the histological and immnuohistochemical structure. Conclusion: Lowering the consumption of aspartame is highly recommended due to the proved toxic effect on the lung and regular intake of kiwi is also advised.