Osteoimmunology suggests that the interaction between macrophages and osteoclasts can regulate bone diseases. Macrophage-osteoclast axis plays an important role in bone immunity. The wear particles produced by artificial joints stimulate osteoclasts to dissolve bone, and macrophages devour wear particles to produce chronic inflammation, leading to aseptic loosening. Macrophages promote fracture healing through anti-inflammatory effect and osteoclast differentiation. Osteoclast activity is the main cause of osteoporosis, in which macrophages play an important role. Macrophages are also considered to be an important cause of excessive osteoclast activity in patients with rheumatoid arthritis. This paper reviews the role of the interaction between macrophages and osteoclasts in bone immunity in related bone diseases.