Abstract: To improve the rate of hydrogen production by proton exchange membrane（PEM）electrolysis and to reduce the energy consumption required for water electrolysis,molecular polarity and stress-strain characteristics of distilled water under a magnetic field were investigated in this paper. By constructing an energy-level transition model of hydrogen proton in the magnetic field and building a mathematical model of relative electrolysis efficiency change of the electrolyzer,it carried out both qualitative and quantitative analyses on the ionic conductivity,electrolyte current density,interelectrode voltage,and hydrogen production efficiency under different magnetic field. Further,the change law of the rate of hydrogen production under different magnetic field conditions was observed and analyzed by using an independently designed adjustable pre-magnetically polarized water electrolysis experimental system. The repeated test results show that the conductivity increases by 2-3 times after distilled water is treated with magnetic polarization,the electrolytic current density of the PEM increases with increasing magnetic field strength,the voltage between the poles continuously decreases,and the hydrogen production rate is significantly improved.