Abstract: Fractal theory was initially proposed in 1970s for describing irregular and complex structures. With the development of science and technology, fractal structure has been widely used in energy, chemical industry, materials and geology etc. nowadays. Particularly, the fluid flow and heat transfer in fractal structure have gradually become a hotspot around the world. First of all, this paper summarizes fractal theory briefly. Then,this paper focuses on the research status in terms of the application of fractal geometry in heat and fluid flow at home and abroad, including tree-like structure, porous media, honeycomb structure and fin structure. And based on the important research mentioned above, discussion is put forward to the enhancement of fluid flow and heat transfer by the use of fractal structure. Finally, it is summarized that fractal theory brings a better way to explain the excellent heat and mass transfer performance of natural fractal structure and is promising in the optimization of heat dissipation structure design.