The paper discusses the treatment results of ten patients with severe atopic dermatitis (AD) who did not respond to standard pharmacotherapy and underwent hyperbaric oxygen therapy (HBOT). Each patient was subject to 10 oxygen exposures at pO2 2.5 ATA (~ 250 kPa) with the duration time of 60 minutes. In the period of implementation of the hyperbaric procedures the general treatment plan was suspended for all patients while maintaining typical local treatment. Clinical evaluation was performed in the study group as well as determination of levels of immunoglobulins: IgA, IgG, IgM and IgE and C3 and C4 complement. All patients indicated clinical improvement and a decreased IgE immunoglobulin and complement C3 level upon the completion of the exposure cycle. Taking into account the authors’ own observations and data from literature, an overall improvement in the clinical status and a decrease in the level of immunoglobulin E and C3 complement following a cycle of exposures may be indicative of an immunomodulating HBOT effect on AD, whereas hyperbaric oxygenation may constitute a therapeutic option for some patients with AD, especially those exhibiting a poor response to standard treatment.