This study was carried out to investigate synthetic extender for semen cryopreservation of Jeju Native Black Bull. The semen was collected using an artificial vagina and transported to the laboratory. The semen was diluted 1:1 by Tris-Egg yolk extender and contrifuged in 1,500 rpm for 15 minutes. The supernatant was removed. The pellect was diluted to final sperm concentration of 2×108/ml by doubling in every 30 minutes at 4℃ cold chamber. The semen was equilibrated for 4 hours at cold chamber and packed to 0.5 ml straw. The semen straws were located above 5 cm for 10 minutes. The height and duration affect the freezing speed by temperature. The frozen straw was plunged to LN2. The presented straws were examined the viability and motility after thawed at 37℃ water bath. Frozen-thawed sperm were evaluated sperm viability, membrane integrity and acrosome integrity. Post-thawed sperm viability has been significantly higher (p<0.05) in fresh sperm (93.27±1.62%) than frozen-thawed sperm (73.34±3.27%). However, there were no significant differences between fresh and frozen-thawed dead cell rate (7.35±2.63 vs, 13.71±2.85). In sperm motility, between Triladyl and AndroMed Extender, there was no significant different (72.86±2.83 vs, 81.47±2.48), similarly, the dead cell rates was similar (18.41±3.42% and 17.26±4.25). The results of our study suggest that AndroMed to the freezing extender showed more positive effect on the frozen-thawed spermatozoa in Jeju Native Black bull semen.