We collected and reviewed sources of amphibian embryo mortality in the present paper. Sources of embryo mort alit v can be divided into two categories: abiotic factors and biotic factors. Abiotic factors include low temperature, excess ultraviolet radiation. desiccation .hypoxia , and low pH value: biotic factors include developmental abnormality, fungi parasitism. and predation. Predation is the key factor of embryo mortality Most predators are facultative polyphagous predators, but some dipterous frogflies have obligate associations with amphibian eggs. So the study of frogflies needs to be concerned by amphibian specialists