To evaluate the effect of positive and negative message framing in diabetes education on attitudes, perceived control, and behavioral intentions toward diabetes self-care, and to identify potential moderating effects of health literacy on message framing.A total of 52 patients with type 2 diabetes that visited an ambulatory endocrinology wing at a university hospital in Korea were randomized into positive or negative message framing groups. Each group watched a 10-minute video that was either positively or negatively framed, accentuating desirable outcomes from good diabetes self-care in the former and undesirable outcomes from inadequate diabetes self-care in the latter. Two-way ANCOVA controlling for HbA1C was conducted to evaluate outcomes.Patients who watched the negatively framed message showed significantly more favorable attitudes and perceived control toward diabetes self-care than those who viewed the positively framed message. Message framing had significant indirect effects on behavioral intentions for diabetes self-care that were mediated by attitudes and perceived control. Conversely, no significant interaction effects were observed between health literacy level and message framing of these same markers.The use of negative message framing in diabetes education is a promising strategy for shaping favorable attitudes, beliefs, and intentions toward diabetes self-care behavior.