Acute ischemic stroke (AIS) is characterized by high morbidity, disability and mortality. In recent years, mechanical thrombectomy has become the standard treatment for AIS with large vessel occlusion, which has also enabled us to collect and analyze the thrombus retrieved from cerebral arteries. Thorough understandings of the type, characteristics and composition of thrombus can not only extend our recognition of the composition of the thrombus, but also help to assist in accurate diagnosis, treatment decision making and secondary prevention of stroke. This paper aims to review for AIS thrombus-relevant literature and propose for further research directions.