To provide a cooler box capable of readily holding a holding part of a handle and easily carriable at the time of transportation.

This cooler box is provided with a box-shaped container body part, a lid part, a hook for hermetically sealing the container body part with the lid part and fixing the lid part thereto and a handle openably and movably connected to the lid part. The handle is a nearly U-shaped member and equipped with a holding part, a pair of leg parts 32a... respectively connected to both sides of the holding part, bent at 90° and formed and mounting parts 33 respectively installed in ends of the pair of leg parts 32a.... The whole mounting parts 33 are bent from the shaft center of the leg parts 32a... in the longitudinal direction and formed.