In order to monitor the developmental features of embryos, larvae, and juveniles of Oryzias latipes (Temminck andSchlegel), Oryzias latipes was caught in river of Shinduck-dong, Yeosu-si, Jeollanam-do, on May 2011, and experiments werecarried out in Ichthyology laboratory at Chonnam National University. The blastodisc step was the first level for natural spawning. The optic vesicle, Kupffer''s vesicle, myotome began to appear 75 hours 57 minutes later. After blastodisc development, thepectoral fins were made at 143 hours 37 minutes and the tail was separated started at the same time. Hatching was observed at167 hours 27 minutes after blastodisc. The total length of the hatched larvae was 4.95~5.10 mm (mean, 5.01 mm), the mouth andanus were opened. Larvae used yolk completely after 3 days after hatching. The total length larvae was 5.45~5.56 mm (mean,5.52 mm) after 8 days after hatching, and appeared the stems for tail. The stems pectoral, anal fin were showed after 14 days andthe stems dorsal, ventral fin were appeared after 19 days. For 35 days after hatching, the total length of larvae 13.95~15.30 mm(mean, 14.64 mm), and at this time, fins and body were transferred like the adult Oryzias latipes.