Health literacy may influence the efficacy of print-based public health interventions. A key part of the U.K. cancer control strategy is to provide information to the public on earlier diagnoses with a view to improving the United Kingdom's relatively poor 1-year cancer survival statistics. This study examined the effect of health literacy on the efficacy of a gynecological cancer information leaflet. Participants (n = 451) were recruited from 17 Cancer Research UK events. Health literacy was assessed with the Newest Vital Sign test. Gynecological cancer symptom awareness and barriers to medical help seeking were assessed before and after participants read the leaflet. Symptom awareness improved, and barriers to medical help seeking were reduced (ps < .001). Symptom awareness was lower in individuals in lower health literacy groups, both at baseline and at follow-up (p < .05, p < .001, respectively), but there were no significant differences in barriers to medical help seeking at either time point (p > .05). As predicted, individuals with lower health literacy benefited less after exposure to the leaflet (ps < .01 for interactions). Despite careful consideration of information design principles in the development of the leaflet, more intensive efforts may be required to ensure that inequalities are not exacerbated by reliance on print-based public health interventions.