Borane clusters represent a unique class of nano-objects not only because of their special coordination and 3D structure but also due to their broad applications ranging from heat resistance coating to cancer therapy agent. Borane cluster-containing polymers (BCCPs) can effectively integrate the merits of both borane clusters and polymers. During the last two decades, with the progress of boron chemistry and the development of advanced polymerization techniques, BCCPs with different architectures and properties have been developed. The introduction of borane clusters into polymeric frameworks not only improves the chemical and thermal stability of traditional polymers but also endows BCCPs with many specific properties, such as photoluminescence, chemical sensing, heat resistance, and boron neutron capture therapy. This feature article gives an overview of the preparation of BCCPs, especially focusing on the design and synthetic methodology. We expect that this review will be helpful to researchers working in the fields of polymer chemistry and materials science.