Human embryonic stem cells (hESCs) have great potentials as a source of cells for cell-based therapies and can be used to develop a system such as toxicology and drug discovery. Human ES research is being conducted with a variety of cell lines and culture conditions, however, the consequence of using such conditions would be confuse in scientific improvement. For this reason, the effort for cell stability and safety used in research work has been recognised and developed by international groups worked for stem cell banking. High-quality stem cell lines confirmed by quality assurance/control and ethically sourced are needed for invaluable stem cell researches and therapies.