Shelter that communication equipment and on-equipment material are mounted on is transported by airplane or vehicle, it has a function such as waterproof and shielding EMI. When the shelter is transported by car or helicopter, it is shocked by vibration and crash with the ground. So, three skids are attached to bottom of the shelter to reduce the shock. To confirm the durability of the structure of shelter, parallel drop and rotating drop test were done in accordance with KDS 0000-0000. However, the damage was discovered in the shelter. So, stiffening plate was added to skid and panel of partition wall to obtain durability and changed the shape of rubber buffer. In this paper, the cause of deformation and damage in the shelter was analyzed and improved shape through the structural analysis was verified.