Cloning, especially human cloning, attracts more and more attention after the first cloning of mammals, the animal Dolly, born in 1997. Cloning is divided into two categories: therapeutic cloning and reproductive cloning. Therapeutic cloning is more related to tissue-level cloning to transplant healthy cells, while reproductive cloning is individual-level cloning. Therefore, the term cloning in this essay is used to describe cloning at both the individual level and the tissue level. The public has different opinions. Some people advocate it for its medical value, but others argue that it could pose many safety risks and moral issues. Therefore, decisions should be made to identify the extent of cloning. Therefore, this essay introduces two important advantages of human cloning in disease therapy and analyzes two arguments against it on ethical and safety issues. First, therapeutic cloning has numerous advantages in treating serious diseases by transplanting healthy cells derived from the patient's body to replace diseased ones. tissues or organs, as well as medical research. One of the advantages is that it can cure numerous diseases, for example, cancer, heart disease, burns and Parkinson's disease. Lindvall (et al., 2011) reports that in 2008, scientists at Memorial Sloan-Kettering Cancer Center successfully treated mice that had a condition such as Parkinson's disease, with cloned embryonic stem cells injected into the mice's brains. Furthermore, this technology can avoid the rejection reaction. Camporesi and Bortolotti (2009) explain that if the transplanted cells are derived from the patient, rather than from a donor, the cells will not be attacked by the patient's immune system as foreign material, therefore the patient will not suffer the adverse effects brought by immunosuppression. ...... half of the article ...... cloning can be divided into two broad categories: potential security risks and moral concerns, and these concerns outweigh its outcomes. In conclusion, with the development of cloning technology, the public has different attitudes towards it. On the one hand, serious diseases, such as liver cancer, can be cured with the transplantation of healthy cells, and scientists have more access to medical research. It brings hope to infertile families to have a baby. On the other hand, it has raised public concerns about safety risks due to the high rate of failures and malformations, and about ethical issues related to dignity, which are mainly caused by productive cloning. Therefore, therapeutic cloning should be strengthened to minimize its potential safety risks so that it can be put into clinical application, while reproductive cloning should be banned worldwide without agreement on moral issues.