The nanomaterial technology with rapid development has become a hot research and application topic in the field of oil and gas well cementing engineering. This article discusses the research and application progress of commonly used nanomaterials and polymer nanocomposites in the field of well cementing. Among them, nanoscale functional materials including silicon dioxide, zeolite powder, halloysite nanotubes, calcium carbonate, clay, magnesium oxide, alumina, carbon nanotubes/carbon nanofibers and grapheme have significant effects on improving the mechanical properties of set cement. However, their application is limited due to the difficulty of dispersing nanomaterials. Polymer latex, nanoemulsion and other organic nanoparticles can significantly improve the channeling prevention performance of cement slurry, the oil washing effect and flushing efficiency of preflush, and play an important role in ensuring the safety and quality of cementing. The modification technology of polymer nanocomposites has been extensively studied in terms of improving the temperature resistance and comprehensive performance of polymer cementing additives. Its comprehensive performance has been greatly improved compared to traditional polymers, and even significant technological breakthroughs have been made. The article proposes suggestions for the research and development of polymer nanocomposite used as cementing admixtures in response to major technical difficulties in complex deep and unconventional oil and gas well cementing. It also proposes product research and development routes from two aspects: nano surface grafting modification and nano intercalation technology, which have an important guiding role in the research and development of key cementing additives. It is expected to promote the progress of complex oil and gas well cementing engineering technology.