With the development of the oral clinical technology and materials, the concept of complex crown root fracture has become more scientific and developed. Epidemiological characteristics, causes and clinical features of this disease are generalized. Aesthetic, functional and minimally invasive coordination is reflected by expounding the diagnosis of complex crown-root fracture, recommendation of treatment and techniques, and characteristics of immature permanent teeth to syste-matize the treatment strategy, and to guide the clinical therapy of complex crown-root fracture.