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 discussed 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 had significant effects on improving the mechanical properties of set cement. However，their application was limited due to the dispersion difficulty of nanomaterials. Polymer latex，nanoemulsion and other organic nanoparticles could 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 was extensively studied in terms of improving the temperature resistance and comprehensive performance of polymer cementing additives. Its comprehensive performance was greatly improved compared to that of traditional polymers. In view of the major technical difficulties in complex deep and unconventional oil and gas well cementing，the research and development suggestions of polymer nano-composite cementing admixture were put forward from the two aspects，such as nano-surface grafting modification and nano-intercalation composite technology，which played an important guiding role in the research and development of key cementing additives with ultra-high temperature resistance and high performance.