Introduction: The prevalence of hypertension in Indonesia has continued to increase over the last few years. An unhealthy diet and lack of physical activity can elevate blood pressure, particularly if an unhealthy lifestyle has been followed since adolescence. This study aimed to analyze the correlation between snack consumption and physical activity with blood pressure in adolescent girls. Methods: A cross-sectional study was conducted with 349 adolescent girls from seven Islamic boarding schools in West Java, Indonesia. Data on daily food and snack consumption were obtained by the 24-hour recall for 3 non-consecutive days. Blood pressure was measured using a digital blood pressure instrument, and the results were categorized by age, gender, and height. Linear regression analyses were performed to investigate determinants of blood pressure. Results: A total of 120 (34.4%) of the adolescent girls in the study had hypertension. A majority of girls had inadequate daily intake (energy, fat, carbohydrates, and sodium; only total protein intake met Indonesia’s recommended dietary allowance). Snacks were found to be high in protein, fat, and carbohydrates, with consumption levels above 15%. More than half (61.9%) of the subjects’ daily sodium intake came from snacks. Low-fat intake from snacks was associated with an increase in blood pressure in this study. Daily nutritional intake affecting blood pressure included sodium and total fat intake. Lack of physical activity in adolescent girls was not a risk factor for elevated blood pressure. Conclusion: Fat and sodium intake was associated with elevated blood pressure in adolescent girls.