Various successes in regenerative medicine by therapeutic cloning have given rise to expectations that treatments will soon be developed for incurable diseases. But using embryonic stem cells for this purpose raises many ethical dilemmas including those about the beginning of human life. Arguments concerning stem cell research and therapeutic cloning in different countries are influenced by both the religious and bioethical traditions which dominate in these cultures. This article examines how these traditions have influenced stem cell research in Iran through an account of scientific advances and the development of regulations on embryonic stem cell research in Iran.