Hot galvanizing is an indispensable process during the production process of galvanized sheet. Compared with traditional hot galvanizing technology, the hot galvanizing electromagnetic enclosed slot technology featured in non-scratch on band steel surface, non-corrosion of sink roll and stabilizer roll, less maintenance and high efficiency, hence it was of vital engineering application value. Firstly, characteristics and significance of electromagnetic enclosed slot technology of hot galvanizing were introduced. Secondly, working principle, research status, technology composition as well as advantages and disadvantages of such technologies of electromagnetic pump type, CVGL electromagnetic enclosed slot type, DC magnetic field type and permanent magnet induction sealing type were introduced. Thirdly, features of complicated coupling among temperature field, flow field, solid structure mechanics field and electromagnetic field were analyzed. Based on technical characteristics of electromagnetic enclosed slot process of hot galvanizing, key technologies including strip vibration suppression technology, suppression technology of liquid zinc unstable flowing, control technology of temperature stability and tension control were put forward. Finally, parameters optimization of electromagnetic device structure, suppression technology of strip vibration and large data-based process control technology were key technologies of improving the working process.