Written educational materials serve as important teaching instruments for prostate cancer patients and their families. However, they must be understandable for their intended audiences. We examined prostate cancer brochures and pamphlets using the Suitability Assessment of Materials (SAM) instrument for the materials' overall suitability, readability, and cultural appropriateness. These factors are crucial to ensure that patients are able to understand and relate to the information. Our evaluation of 29 materials demonstrated that the majority, 22 (75.8%), scored "adequate" for their overall suitability. However, 26 materials (90%) scored "not suitable" for their reading grade level, while 55% of the materials could not be rated on cultural appropriateness because of lack of cues about the intended audience. Also, many of the materials scored poorly on content, graphics, self-efficacy, and learning motivation and stimulation. Most of the materials did well with typography and layout. Overall, the findings point to the need to carefully assess written materials used for multicultural audiences with low reading ability.