Multi-path transmission technology establishes multiple transmission paths between communication parties via various network interfaces on devices. In this way, bandwidth aggregation, load balance, and path redundancy will be achieved to increase transmission throughput and reliability. These benefits allow the multipath transmission technology to be widely used in several application scenarios such as servers, terminals, and data centers. As a part and parcel of network architecture and transmission technology studies, the technology is of research significance and value. To this end, this study systematically analyzes the multi-path transmission technology in terms of its concepts and core mechanisms. Firstly, the basic concepts, standardized process and application value of multi-path transmission are outlined. Secondly, the core mechanisms of the multi-path transmission technology are enunciated, including congestion control, packet scheduling, path management, retransmission mechanism, security mechanism, and the mechanism for specialized applications. Classification methods and the main research results of each mechanism are elaborated, and the advantages, disadvantages and the development direction of mechanisms are summarized. Finally, this study probes into challenges faced by multi-path transmission technology research and envisions the prospect for relevant studies.