The behavior of an expansion of balloon-expandable stent is in three-dimensional space. Therefore, it is necessary to observe in three-dimensions, however little previous research measures this behavior in three-dimensional space. Micro-CT is an image device that can observe more accurately with three-dimensions than the conventional CT. We reconstructed the stent shape using the medical image obtained by Micro-CT in three-dimensions. We observed the behavior of stent and the elastic recoil of stent (ERS), and measured ERS quantitatively. This aim is to observe the three-dimensional expansion behavior and ERS using Micro-CT, and evaluate quantitatively. We observed the three-dimensional expansion behavior of stent. Despite, the similarity of structures, the expansion behavior of stent and ERS were different in each structure. Moreover, we evaluated ERS quantitatively in proximal and distal of each structure influence from the balloon pressure. ERS ratio ranged from 4.7 % to 6.7 % in proximal and distal. When dividing stent into two in the direction of the length axis, ERS is shown proximal < distal in structures 1st to 3rd, and ERS is shown proximal > distal in structures 4th to 6th. And it reduces in the direction of a minor axis by maximum ERS 5.7%. We observed three-dimensional behavior of balloon-expandable stent and the ERS, and evaluate ERS quantitatively using Micro-CT. We found that it is necessary to observe in three-dimensions.