Purpose: This review summarizes the methods employed to evaluate denture cleansers and makes some suggestions on the methodology of evaluation. Materials and Methods: More than 20 articles evaluating the efficacy of denture cleansers were compared, and the advantages and disadvantages of each method were evaluated. Results: The results obtained vary depending on the methods used to evaluate the efficacy of denture cleansers, particularly among in vitro and in vivo assays. In addition, it is pointed out that chemical denture cleansers are not as efficacious in clinical use as in the in vitro assay. The uncertainty over efficacy may be caused by nonstandardized methodology and reports of conflicting results. Conclusion: A standardization of the methodology is needed. This should include evaluation of the efficacy of cleansers through both in vivo and in vitro assay methods; standardization of the materials and methods used in studying the efficacy of denture-cleansing regimens; and the examination of not only selected microorganisms from limited surface areas of a denture, but the microorganisms in denture plaque from the whole surface of a denture. It would also be preferable to use methods and/or media that make it possible to not only qualify but also quantify the microbial plaque.