Abstract: Microreactors have been widely applied in many fields such as chemical, pharmaceutical, environmental, materials, metallurgy, energy, and medical diagnosis industries due to these advantages, for example, small volume, high heat and mass transfer performances, high security, and good controllability. Therein, the global researchers have always focused on intensification of mass transfer and reaction in the microreactors. The structure of microreactors, the enhancements of ultrasonic field, centrifugal field, magnetic field, light and stir have been systematically reviewed. Then, the reasons of intensification of mass transfer and reaction in the microreactors have been in-depth analysis. Finally, the development trends on intensification of mass transfer and reaction in the microreactors have been prospected. In order to enhance mass transfer and reaction in the microreactors, the following measures may be taken: （1） The formation mechanism of droplets, liquid slugs, liquid flows, bubbles, gas slugs and gas flows, and affecting factors and transformation mechanism of fluid flow pattern in the microreactors have been in-depth-study. （2） The satisfactory reinforcement effect will achieve by using the coupling measures. For example, integration of spiral microchannels and ultrasonic field, combination of spiral microchannels and photocatalysis, and integration of gas stir and rotating microchannels. （3） The performance optimization and improvement of microreactors have been realized through numerical simulation, experimental study, and scale-up process. The ultimate aim is the application of microreactors in industrial production.