A combined abdominal aorta covered stent system and a utilization method thereof are applied to surgeries for endovascular interventional treatment of abdominal aortic aneurysm. The system comprises a body covered stent and a pair of branch covered stents, and each of the stent is cylindrical and provided with a delivery system. The near end of the body covered stent is a bare stent with barbs, a covered section comprises an upper half portion in a single-cavity cylinder shape and a lower half portion with a fixed outer diameter, and the lower half portion is averagely partitioned into two cavities by a longitudinal partition. Small-waveband stent rings are designed at near and far ends of the covered section of the body covered stent, and other covered parts can be either provided with stent rings or not. The upper half portion of the covered section is implanted at a neck position of infrarenal aortic aneurysm, and the lower half portion is suspended in an aneurysm cavity. The branch covered stents parallelly and internally sleeve the two cavities of the body covered stent, near ends of the branch covered stents are flush with the near end of the lower half portion of the body covered stent and fill the cavities of the body covered stent in a self-adoption manner, and far ends of the branch covered stents are implanted into iliac artery branches to better adapt to arterial aneurysms excessive in aneurysm neck torsion.