Background: The retinacular arteries provide major supply to the femoral head, their injuries may lead to the femoral head necrosis (FHN) in femoral neck fractures. Although the femoral neck fracture was seriously displaced in some patients, FHN did not occur, which suggests that the blood supply is not fully blocked. This study was aimed to find the association between the structure of the retinacula of Weitbrecht and the mechanism of protecting retinacular arteries from being injured. Materials and Methods: Fourteen formalin-fixed cadaveric specimens (in 28 hips) with no significant vascular disease were observed. The retinacula were cut longitudinally and then cut into three parts: medial, middle, and lateral. These specimens were stained using hematoxylin and eosin and improved Masson Trichrome stain. The microstructure and tightness of the retinacula fixed to the bone and the distribution of vessels were examined under a stereoscope, an optical microscope, and a scanning electron microscope. Results: The microstructure and compactness in each part of retinacula were different, and the tightness of the fibers of the retinacula fixed to the bone in each part were different. A particular structure which resembled a Sandwich panels was observed, and it may be an effective mechanism of protecting retinacular arteries. Conclusion: The Sandwich panels structure existed generally in the retinacula of Weitbrecht, and this sandwich panelture may play very important role in protecting the retinaculum artery from being injured, which show the importance of protecting the retinacular artery in the treatment of femoral neck fractures.