Needle retention duration, as an essential link in acupuncture treatment, has always been valued by physicians in all ages of the Chinese history. In this article, related literatures in recent years on influence factors of needle retention duration have been collected and reviewed in terms of duration, type and state of illness, point selection and so on. Modern related researches, to a certain extent, have approved and advanced the viewpoints of the previous physicians. However, few of the studies are randomized controlled trials of evidence-based medicine. Most of them still remain in observation stage. Therefore, scientific designing methods should be adopted in the future for researching approaches of TCM. Systematic and through studies should be carried out on needle retention duration, so as to comprehend the principle and define the optimal duration for different diseases. In this way, a standardized and systematic model on acupuncture treatment can be established.
