This study was conducted to investigate the effects of capacitating agents added at in vitro fertilization (IVF) and antioxidants supplemented during in vitro culture (IVC) on the development of buffalo embryos. In experiment I, in vitro embryo development of buffalo embryos was compared when the IVF medium was supplemented with heparin, caffeine and calcium ionophore A23187 either alone or in combination. There was no significant difference (P > 0.05) in the cleavage rates of oocytes among the treatment groups but the development rate to the blastocyst stage and the cell numbers of blastocyst in the heparin-treated group were significantly higher (P < 0.05) than that of other treatments. In experiment II, in vitro embryo development of buffalo embryos was compared when IVC medium was supplemented with either α-tocopherol (250 and 500 μM) or l-ascorbic acid (250 and 500 μM). The rate of development to the blastocyst stage of embryos cultured in medium supplemented with 250 μM α-tocopherol (33%, 41/123) and 250 μM l-ascorbic acid (31%, 38/123) was significantly higher (P < 0.05) than that of those cultured in medium alone (19%, 20/108) but not significantly different (P < 0.05) from medium supplemented with either 500 μM α-tocopherol (24%, 30/123) or 500 μM l-ascorbic acid (25%, 33/133). These results suggest that buffalo spermatozoa treated with heparin were suitable for IVF and that α-tocopherol and l-ascorbic acid added during IVC increased the rate of buffalo embryo development.