An involuntary autobiographical memory (IAMs) is a memory of a personal experience brought to consciousness with apparent spontaneity, that is, without preceding attempts at retrieving it. This article presents and talks about four aspects，which are research methods of IAMs, three special properties of IAMs, the correlative theories and the future research emphasis and difficulties. Firstly, in this article presents research methods of IAMs. According to the memory content’s traumatic ,the IAMs consists of non-traumatic IAMs and traumatic IAMs (intrusive memory) .The research methods about non-traumatic memory are developed from the initial structure diary method to word-association task and vigilance task paradigm, the later are mainly used in laboratory. So far the structure diary method is the most classic research method, which is widely used in the property research of IAMs. Stressful film paradigm is worth learning for non-traumatic IAMs research method development. Secondly, the paper shows three special properties of IAMs and talks about how to explain them. The IAMs is the same as the voluntary autobiographical memory in many basic properties in the early studies. However, researchers not only did find the special features of the IAMs but also provided direct evidences for its theory construction. They are direct retrieval, content-specificity, and emotion-impact. The content of IAMs is about the specific event of personal life and has intensely emotional influence to human. They are content-specificity and emotion-impact. Their presence is based on the different reasons. Content-specificity’s presence is because a part of content of IAMs has not been integrated to the high-order autobiographical knowledge base and is linked intensively to cue. But it is the instant experience when retrieves IAMs that causes to happen emotion-impact. An involuntary autobiographical memory (IAMs) is a memory of a personal experience brought to consciousness with apparent spontaneity, that is, without preceding attempts at retrieving it. This article presents and talks about four aspects，which are research methods of IAMs, three special properties of IAMs, the correlative theories and the future research emphasis and difficulties. Firstly, in this article presents research methods of IAMs. According to the memory content’s traumatic ,the IAMs consists of non-traumatic IAMs and traumatic IAMs (intrusive memory) .The research methods about non-traumatic memory are developed from the initial structure diary method to word-association task and vigilance task paradigm, the later are mainly used in laboratory. So far the structure diary method is the most classic research method, which is widely used in the property research of IAMs. Stressful film paradigm is worth learning for non-traumatic IAMs research method development. Secondly, the paper shows three special properties of IAMs and talks about how to explain them. The IAMs is the same as the voluntary autobiographical memory in many basic properties in the early studies. However, researchers not only did find the special features of the IAMs but also provided direct evidences for its theory construction. The special features are emotion-impact, content-specificity and direct retrieval which mean that the IAMs is a kind of direct retrieval autobiographical memory. Their presence is based on the different reasons. Content-specificity’s presence is because a part of content of IAMs has not been integrated to the high-order autobiographical knowledge base and is linked intensively to cue. But it is the instant experience when retrieves IAMs that causes to happen emotion-impact. Thirdly, the article talks about the correlative theories of IAMs. Later developed global work space intelligent distribution theory shows that the IAMs results from the connection between representation set of clues and long-term memory content. This theory explains the rule of memory generation but not have a good explanation to the special features. Traumatic IAMs theories include dual representation theory and cognitive model theory. The two theories both have a good explanation to the formation of traumatic memory and performance of traumatic memory, meanwhile provide an induction for the treatment of clinical diseases. At last, the author discusses the future research emphasis and difficulties of IAMs. Research about IAMs should focus on three aspects: particularity qualitative interpretation, the integration of memory structure and exploration of memory function. (1)The interpretation of special features conclude two parts, one research probe into the principle of matching procedure in direct retrieval, the other study the impact factor of different rate of specific memory content. (2)The integration of the memory structure is to develop a unite theory about IAMs. (3)There are two functions for IAMs enlarging knowledge and mental defense. Retrieval of IAMs is a reintegration process, consequently the process will increase autobiographical knowledge base, and on the other hand, retrieval of IAMs can lighten and transform the negative memory and traumatic memory. At last, the author discusses the future research emphasis and difficulties of IAMs. Research about IAMs should focus on three aspects: particularity qualitative interpretation, the integration of memory structure and exploration of memory function. (1)The interpretation of special features conclude two parts, one research probe into the principle of matching procedure in direct retrieval, the other study the impact factor of different rate of specific memory content. (2)The integration of the memory structure is to develop a unite theory about IAMs. (3)There are two functions for IAMs enlarging knowledge and mental defense. Retrieval of IAMs is a reintegration process, consequently the process will increase autobiographical knowledge base, and on the other hand, retrieval of IAMs can lighten and transform the negative memory and traumatic memory.