Dizziness in 15-year-old girls may be caused by lack of sleep, mental stress, low blood pressure, anemia and other reasons. 1. Lack of sleep: if 15-year-old girls play with cell phones, computers, stay up late, overwork or lack of sleep, it may lead to nerve function disorders in the brain and symptoms of dizziness. 2. Mental tension: Due to the high pressure of study at this stage, patients are prone to mental tension and anxiety, leading to vegetative nerve dysfunction and symptoms of dizziness, which may also be accompanied by mental fatigue, memory loss and other symptoms. 3. Low blood pressure: When 15-year-old girls have low blood pressure due to heredity, partiality, picky eating, weight loss and other reasons, it will easily lead to a reduction in the blood supply to the brain tissue, resulting in insufficient blood and oxygen supply to the brain, dizziness, general weakness and other symptoms. 4. Anemia: If a 15-year-old girl has malnutrition, it may lead to anemia, often accompanied by dizziness and pallor. When a 15-year-old girl has dizziness, parents should immediately take the girl to the hospital, clarify the cause of the disease and follow the medical advice.