Objective To observe the histomorphlogical changes of the collagen fiber structure after the articular cartilage was subjected to loading. Methods The articular cartilage specimenns from 12 human femoral heads were studied under scanning electronic microscope to observe the structure changes under different sets of loadings. Results The collagen fibers tended to become bended when they were subjected with loadings.The bending of the fiber became more marked and finally disrupted as the loads increased. Conclusion When the articular cartilage is loaded with abnormally high stress,it may result in damage or even cause the disruption of the collagen fibers.