Dizziness and weakness of legs are commonly caused by anemia, viral infection, fever, low blood pressure, low blood sugar, and insufficient blood supply to the brain. 1. Anemia is mostly caused by a decrease in the hemoglobin content of the blood in the body. Generally, early anemia does not cause any obvious discomfort, but as the anemia is not corrected in time, it can develop into moderate and severe anemia, and at this time, symptoms of dizziness and weakness of legs can easily appear. 2. When you have a cold or fever, the body cannot tolerate the body temperature due to the increase in body temperature, which can cause dizziness and weakness of legs at this time. 3, hypotension, hypoglycemia can cause a decrease in the oxygen supply to the brain, resulting in symptoms of dizziness, weakness of the legs. 4, some women have menstruation or endocrine disorders, the amount of menstruation is not larger, resulting in heavy bleeding, which can also cause dizziness, weakness of the legs. 5, calcium deficiency, poor rest, stress, excessive tension, shock can also lead to dizziness, weakness of the legs. Since there are many causes of dizziness and weakness, patients need to go to the hospital early for systematic examination to clarify the cause and timely treatment to avoid greater harm to the body.