The original state of the core is the most ideal sample for geological analysis, but the core is fragile in broken and well developed fractured formations, it is easy to be misplaced when taking out of the inner core barrel and difficult to maintain the original sedimentary state of the formation, which is not conducive to obtaining accurate geological information. In order to solve this problem, a study was carried out on the inner barrel protection technology of coring tools for fractured formation. By designing a set of inner barrel transporting device, matching with spring shock absorption mechanism and grease injection packaging technology, the effective protection of the core during the transportation of the inner barrel is realized. The direct contact between the inner barrel and the external environment can be reduced during the core transportation, the collision of the core during the transportation can be avoided, and the secondary damage probability of the fragile core is reduced. The field application of more than ten wells proves that the technology can effectively ensure the physical nature integrity of broken core and provide more reliable original data for geological analysis.