Livestock embryo production in in vitro systems has been highlighted due to the emergence of interest in embryo stem cells (ESC). ESC potency and their wide potential applications have been recognized in medicine, fundamental research fields and commercial markets due to ESC totipotency or pluripotency and self-renewal. Ovine ESC probably is a useful technical platform for transgenic livestock and animal cloning, but ESC lines have not yet been founded because of difficulties in ESC isolation and the lack of blastula materials. We have established an IVP (in vitro production) system in our laboratory, including in vitro maturation, in vitro fertilization and in vitro culture, to produce sheep blastula using fresh ovaries and testes collected from livestock production. This system can achieve rates of mature eggs and blastulas of 65 and 50% respectively, and can provide enough blastulas for ICM (inner cell mass) isolation. Furthermore, ESC-like clones were isolated from the ICM on ovine embryonic fibroblast (OEF) feeder cells and in ES-DMEM supplemented with the cell factors LIF and SCF, and these survived to the third passage, which was primarily identified by AKP staining and morphology. This work provides a basis for ovine ESC isolation and foundation of ESC lines.