Background: The purpose of this study was to verify the effectiveness of the selected bio-resonance method under in- vitro conditions. The question of alternative therapies efficiency is very important in situation when traditional therapies may be not enough effective. In such situations, patients reach for alternative solutions and sometimes even physicians suggest their application.Methods: In the article, the authors present results of a neutralization method efficiency of selected pathogens using selected bio-resonance method. The verification of the method was conducted with usage of a constructed generator. The generator strictly realized a signal described in the literature associated with the bio-resonance topic. The authors carried out tests in in- vitro laboratory conditions on material including both clinical and reference strains of both bacteria and fungi.Results: According analysis of 24 test series of the bacterial and the fungi strains, the samples treated with the generator did not show a significant decrease of the pathogen population in relation to the comparative samples. Generally accepted standards in microbiology, describes a significant reduction of the pathogen population appears when the population size decrease at least about one order of magnitude in relation to the comparative samples.Conclusions: As a result of the tests, the ineffectiveness of the tested method was demonstrated. This is an important result because this method is considered as effective in many environments, and patients based on this fact, often give up conventional treatment.