The present study provides direct experimental proof that the combination of influenza virus infection A/Aichi/2/68 (H3N3) with different models of oxidative stress, such as immobilization, cold and cold-restraint, is associated with graduated oxidative disturbances in the stomach of mice, despite the absence of virus replication and inflammation in this tissue. It was found that experimental influenza virus infection is accompanied with significant changes in gastric mucosal integrity, as well as an increase in the products of lipid peroxidation in the stomachs of mice. Preliminary exposure of mice to immobilization stress and subsequent inoculation of influenza virus did not significantly influence gastric ulceration or lipid peroxidation compared with infected mice. Cold stress resulted in a significant decrease in the index of stomach ulceration and did not influence the fluorescent products of lipid peroxidation and MDA compared with infected animals. The simultaneous application of cold-restraint stress and influenza virus infection provoked synergism in the activity of all factors on the parameters under investigation. Ulceration increased approximately two-fold, as did the amount of fluorescent products of lipid peroxidation and MDA, compared with influenza virus-infected and non-stressed animals.