Background <p>Gestational diabetes mellitus (GDM) is a prevalent pregnancy complication and a growing public health concern due to its increasing prevalence and its short- and long-term consequences for maternal and neonatal outcomes. Beyond medical treatment, awareness of healthy lifestyle behaviors plays a critical role in effective disease management and prevention of complications.</p> Objective <p>This study aimed to evaluate healthy living awareness levels among pregnant women diagnosed with GDM and to examine their association with sociodemographic and obstetric characteristics.</p> Methods <p>This hospital-based, descriptive cross-sectional study was conducted between February and April 2023 at a tertiary care center using a structured questionnaire. A total of 189 pregnant women diagnosed with GDM at ≥ 24 weeks of gestation were included. Data were collected via face-to-face questionnaires, and healthy living awareness was assessed using the 15-item Healthy Living Awareness Scale (HLAS). Group comparisons and correlation analyses were performed using appropriate statistical tests.</p> Results <p>The mean total HLAS score was 62.3 ± 6.0, reflecting a moderate-to-high level of healthy living awareness. Higher educational attainment, employment status, primiparity, and planned pregnancy were significantly associated with higher HLAS scores (all <i>p</i> &lt; 0.01). No significant differences were observed according to age group, previous GDM history, or treatment modality. A weak but statistically significant negative correlation was found between body mass index and HLAS scores (<i>r</i> = − 0.165, <i>p</i> = 0.023).</p> Conclusion <p>Healthy living awareness among women with GDM varies across sociodemographic and obstetric subgroups. Identifying women with lower awareness may support the development of targeted public health strategies and personalized health interventions during the preconception and antenatal periods.</p>