Successful human reproduction requires normal development of oocyte, sperm and early embryos. The abnormality and dysfunction in any of these processes will result in infertility. We mainly focus on molecular mechanism of physiology and pathophysiology in the development of human oocytes, fertilization and early embryos. We focused on investigating genetic reasons of oocyte maturation arrest, fertilization failure and early embryonic arrest. We also strive to elucidate corresponding molecular mechanism regulating the phenotype of oocyte spindle assembly, chromosome segregation, which are essential for normal oocyte maturation and embryonic development. By using methodology of medical genetics，cell biology as well as functional genomics, we seek to identify disease-causing mutant genes, key physiological genes for physiological and pathophysiological phenotypes in oocyte and embryonic development and figure out corresponding molecular mechanism. In our research, clinical samples, mouse model, even monkey model are commonly utilized.