Human research on islet cell transplantation for the treatment of diabetes has been going on for more than 30 years. It has gone through the stages from animal experiments to human trials and finally applied in the clinic. In the past, islet cell transplantation mostly used human fetal pancreatic cells, but due to a series of problems such as difficulties in the source of human fetal pancreatic cells, developmental defects and immune rejection, islet cell transplantation was once at a standstill. Canadian scientists first completed adult islet cell transplantation to treat type 1 diabetes and achieved success. This result stirred the world and showed people a new hope for curing diabetes, and from then on set off the islet cell transplantation craze. Later, the first adult islet cell transplant was successfully performed in China. The recipient of the transplant was a 12-year-old child with type 1 diabetes who had been living on insulin injections three times a day for many years. Islet cells voluntarily donated by the families of two deceased persons were transplanted into her body twice. After a year of observation and treatment, the child no longer needed exogenous insulin injections and recovered well. However, there are many complex issues that need to be addressed to make islet cell transplantation a widely effective treatment for diabetes. For example, the lack of islet tissue sources; the complexity of islet cell isolation and purification techniques; and the immune rejection of the implanted islet cells by the organism, etc., are problems that seriously hinder the widespread use of islet cell transplantation. One of the main problems is how to avoid the body’s attack on foreign transplanted cells and eventually kill these cells. This is a normal immune defense response that has evolved over time in humans. The current clinical approach to combat this problem is the application of strong and forceful immunosuppressive agents, and the toxic damage to islet cells and the carcinogenic effects of some agents associated with the application of immunosuppressive agents is another challenge that needs to be addressed. In recent years, researchers have tried to use molecular biology techniques to construct replaceable grafts to solve the problem of insufficient islet tissue sources. The use of genetic recombination and transgenic techniques to transfer insulin genes into other cells to produce insulin-secreting cells is one of the methods that have been tried to solve the lack of islet cells. With the rapid development of human stem cell research and breakthroughs in stem cell technology, it will certainly lead to large-scale in vitro expansion of human islet stem cells and the establishment of islet stem cell banks, which is expected to overcome the shortage of donor islets, an obstacle limiting the widespread development of islet cell transplantation. In addition, the construction of immune barrier of islets with biofilm and the development of new immunosuppressants and immune tolerance inducers are expected to solve the problem of immune rejection and improve the success rate of clinical islet transplantation, bringing a bright future for the treatment of diabetes. There is still no clinical cure for diabetes, because diabetes is due to the damage received by the body’s pancreas, so there is no basis for many claims that diabetes can be cured. However, the medical community is still working tirelessly to cure diabetes. However, many type 2 diabetes is caused by obesity, and although the pancreas is damaged, if weight loss reduces the burden on the pancreas, insulin in the body can still maintain a stable blood sugar level. This is called “complete remission”, so in the absence of a cure for diabetes, some of us obese people with type 2 diabetes can get remission through weight loss or surgery.