An abdominal aortic aneurysm of 4.8cm is not normal. Generally, an abdominal aortic aneurysm is diagnosed when the diameter of the abdominal aorta is greater than 3cm. Abdominal aortic aneurysm refers to the permanent limited or diffuse expansion and bulging of abdominal aorta. If the aneurysm increases in size, it will compress the surrounding tissues and organs and the corresponding compression symptoms will appear, such as abdominal pain, swelling of the lower limbs, obstructive jaundice, etc. Therefore, abdominal aortic aneurysm with a diameter of 4.8cm is not normal. If the diameter of the tumor is less than 4cm, ultrasonic follow-up observation can be taken temporarily; if the diameter of the tumor is greater than 5cm or the annual growth rate is greater than or equal to 1cm, it should be treated by surgery as early as possible. If the tumor diameter is 4.8cm, it is still controversial whether surgery is needed, but ultrasound or CTA examination should be performed at least once a year to avoid rupture and bleeding due to the rapid growth of the tumor. When an abdominal aortic aneurysm is detected, it is recommended to seek prompt medical attention, be evaluated by a professional doctor, and follow the doctor’s instructions for regular monitoring or treatment to avoid delays.