Recently, great efforts have been made to explore high-performance microwave absorbing (MA) materials, which aim to reduce the booming electromagnetic wave (EMW) pollution caused by electronic devices. MXenes (i.e., two-dimensional (2D) transition metal carbide/nitride), an emerging family of 2D nanomaterials, demonstrate superiority to conventional nanomaterials, such as tunable electrical conductivity, unique layer structure, abundant terminal groups, and great physico-chemical properties, becoming potential candidate materials for high-efficiency MA. By hybridizing MXenes with other lossy mediums and designing novel microstructures, MA properties can be further optimized and enhanced for practical applications. Furthermore, MXene-based materials, with smartly designed multi-functionality, become a research priority to develop new or advanced applications for the coming “intelligent era”. This review focuses on using MXenes to effectively absorb EMW energy. In the first part, the fabricating methods of MXenes are systematically introduced followed by a second part on the progress of MXene-based materials regarding the MA performances, as well as a summarization on their next-generation smart multifunctional materials. In the final part, opinions on the future perspectives and opportunities of MXene-based MA materials are presented. It is believed that this review will pave the way for further flourishing the development of MXene-based materials in MA field.