Prospective memory means that remembering to execute planned events or acts at a time in the future. Prospective memory processing involves complex cognitive processes. Although 一n recent years, we obtain a lot of achievements in prospective memory, its neural mechanism is still a mystery. Clinical researches on prospective memory provides a lot of important empirical evidences, and thus becomes one of the important ways to study the neural mechanisms of prospective memory. This paper summarized the related literatures of prospective memory brain mechanisms and introduced the role of the prefrontal cortex, thalamus, medial temporal lobe and other brain regions in prospective memory. From clinical point of view, we analyzed the neural mechanisms of prospective memory through researching on the studies of the prospective memory of the Attention Deficit/Hyperactivity Disorder children, patients with Alzheimer's disease, Alcohol Dependency Syndrome and Medial Temporal Lobe Epilepsy patients. The evidences showed that the prefrontal cortex is mainly responsible for encoding, retrieving and monitoring processes in prospective memory, also has a close relationship with the intentions maintaining. The hypothalamus is related with the intentions implementation, and its interactions with the prefrontal cortex plays an important role in prospective memory monitoring. The medial temporal lobe is involved into the retrieval of the encoding source. There is a close relationship between the medial temporal lobe and the intentions activating. Researches displayed that the four stages of prospective memory processing are damaged for Attention Deficit/Hyperactivity Disorder children, and the intention formation stage was damaged heavily. Patients with Alzheimer's disease, whose prefrontal and medial temporal lobe was damaged, and they are difficult in identifying clues and maintaining intentions. The prefrontal cortex and thalamus of Alcohol Dependency Syndrome patients was injured. These patients can be aware of their prospective memory impairment, but it seems that they can’t adore some internal or external strategies to address these deficiencies. The ability of intentions activating of the patients of Medial Temporal Lobe Epilepsy was impaired, and the link between the cues and the intentions has been violated. This study suggests that the prefrontal cortex may be involved in all the stages of prospective memory process and it may play a central role in the prospective memory processing. Studies also show that the prefrontal cortex as well as the interaction among some brain regions: prefrontal cortex, thalamus and medial temporal lobe maybe the neural basis of prospective memory encoding, maintaining, retrieving and implementation.