Type 2 diabetes mellitus is a chronic disease with a steadily increasing prevalence that requires optimal medication adherence to prevent long-term complications. The rapid expansion of digital health technologies has improved public access to health information, yet differences in digital health literacy may influence patients' ability to obtain, evaluate, and apply health information to support medication adherence. This study aimed to examine the relationship between digital health literacy and medication adherence among patients with type 2 diabetes mellitus attending primary healthcare centers. A quantitative analytical study with a cross-sectional design was conducted involving 180 patients selected through consecutive sampling. Data were collected using the Digital Health Literacy Instrument (DHLI) and the Morisky Medication Adherence Scale (MMAS-8). Statistical analyses included the Chi-square test and multivariable logistic regression with a significance level of 0.05. The findings indicated that patients with higher digital health literacy were significantly more likely to demonstrate good medication adherence than those with lower literacy levels (p<0.001). Furthermore, digital health literacy remained an independent predictor of medication adherence after adjustment for age, educational level, and duration of diabetes. These findings highlight the importance of strengthening digital health literacy in primary healthcare settings to improve diabetes self-management and support the development of evidence-based digital health education programs for patients with chronic diseases.