Guppy has become a model organism for studying behavioral traits such as courtship and mate choice, as well as for understanding ecogeographic adaptation. Unfortunately, studying the early development of live bearers is more complicated than that of oviparous species, due to the inaccessibility of developing embryos for experimental manipulation. Ulrike et al. showed that the embryos could not be cultured for the entire period of their embryonic development. To optimize conditions embryo in vitro culture we established system for varying the concentration of fetal bovine serum in the medium impact on the embryonic development of in vitro embryos. For in vitro culture, embryos were incubated in 8 ml of sterile embryo medium (L-15 [Leibovitz] medium, supplemented with 5, 10, 15, and 20% fetal bovine serum respectively, 20 units/ml penicillin, and 200 mg/ml streptomycin) in a dark incubator at 25℃. Our study found that in 5% of FBS of the medium, embryos can be maintained until the middle-eyed. In 10% and 15% embryos can be maintained constant development; some of them can be fed; however, in 15% it is faster than 10%. And although in 20% of FBS can sustain rapid development of early stage, but ultimately died. According to our experimental data, both 10% and 15% FBS in medium can be used for in vitro culture, the slowly development in 10% FBS appears to be more conducive to observation.