Abstract: To improve the safety of marine and offshore engineering structures, this paper adopts tests in cluding hydrogen permeation, hydrogen micro printing, thermal desorption and slow strain rate tensile to analyze, the laws of hydrogen atom diffusion, hydrogen trap distribution and hydrogen embrittlement sensitivity variation of DH36 steel under different hydrogen charging conditions. The results indicate that under electrochemical hydrogen charging at a current density of 10 mA/cm², the densities of reversible hydrogen traps and irreversible hydrogen traps in the DH36 steel are 3.12×10¹⁸ cm^-3 and 2.09×10¹⁸ cm^-3, respectively. Hydrogen atoms mainly exist at grain boundaries and inclusion positions, with less distribution within grains; and with the increase of hydrogen charging time, the aggregation degree of hydrogen atoms at grain boundaries and inclusion positions increases. When the hydrogen charging time is 8 min and 80 min, hydrogen desorption peaks occur at 65.2 ℃ and 445.6 ℃, and at 28.7 ℃ and 470.5 ℃, respectively, and as the hydrogen charging time increases, the desorption amount of hydrogen atoms increases. As the hydrogen charging time gradually increases to 80 min, the yield strength and tensile strength first increase and then slightly decrease, the elongation continuously decreases, and the hydrogen embrittlement sensitivity continuously increases.