During the oocyte maturation, antioxidants may be beneficial for futher developmental competence against reactive oxygen species (ROS) because the media for oocytes lack boiomolecules that serve as scavengers. In this study, N-acetyl-L-cysteine (NAC), N-acetyl-L-cysteine amide (NACA), glutathione (GSH) and cysteamime were compared to determine the effects of protection for ROS from GV to MII stage when supplemented during in vitro maturation (IVM) and in vitro culture (IVC) of bovine oocytes. NAC is one of well known ROS scavanger and NACA is modified form of NAC to help permeation into cytosolic area of oocytes. Significant improvement on the development undergoing blastocysts (32%, vs 18%, 22%) were found when cysteamine (0.1mM) was added to the maturation medium than NAC (0.3 mM), NACA (0.2mM) or GSH (0.5 mM) as compared to control medium with antioxydents. However, the addition of NAC(18%) or NACA(21%) to media did not improve the proportion of oocytes undergoing development to morula and blastocysts than control (24%) and GSH (26%). Our study showed that medium supplementation with cysteame during IVM and in vitro culture (IVC) improved the rate of bovine embryo development, in contrast to extracellular antioxidants like NAC, NACA and GSH that caused no improvement.