The effect of several potential antioxidants and amino acids were examined as a means of increasing the development of in vitro matured and in vitro fertilized oocytes into morulae or blastocysts. Bovine embryos developed to the 2~8 cell stage after in vitro fertilization were cultured for 5 to 6 days at 39$^{circ}C$ in CR1aa containing varing concentraton of the antioxidants and amino acid in a gas phase consisting of 5% CO2, high humidified air. At 5~6 days, embryo developments were reduced, and embryos were fixed and stained with Hochest 33342 DNA stain to facilitate counting of cells. In experiment 1, the proportion of embryos developed to morulae and blastocysts in CR1aa containing 1mM, 2.5mM taurine (22.6% and 20.4%) was slightly higher than those of 0, 5 and 10mM Taurine (5.7, 5.7 and 3.9%, P<0.05). In experiment 2, addition of glutathione did not improve blastocyst development (P>0.05). In experiment 3, concentations of superoxide dismutase(SOD) ranging from 300 to 1,000 U did not affect the propotion of embryos developing into blastocysts (P>0.05). In experiment 4, addition of 250 U catalase(38.5%) was slighty higher than those of 0, 500 and 1,000U. In experiment 5, the proportion of embryo developed beyond morula stage in CR1aa with taurine plus EDTA was slighty higher than other treatments(15.7, 26.0 and 29.2%), there were no significantly increases in cell number among treatments(P>0.05). These results are indicating that antioxidants and amino acids can increase the proportion of embryos that develop into morulae and blastocysts, but did not increas in cell number of blastocysts.