The technique of cryopreservation of fish embryos has not efficient results yet, however, the cooling of embryos has been used with satisfactory results. The aim of this study was cooling embryos Colossoma macropomum subjected to a temperature of 2ºC at different times of storage. Embryos were used in the following embryonic stages: blastoderm - 1.2 hours post-fertilization (hpf), epibolia - 5-hpf; closing blas...