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In the present study, the very high cycle fatigue properties of two high strength martensitic steels containing two different types of (Ti,Mo)C precipitates with and without electrochemical hydrogen charging were investigated. Results revealed that spherical undissolved (Ti,Mo) particles and non-metallic inclusion with a hydrogen desorption activation energy of 142.6 and 70.9 kJ/mol, respectively could not trap hydrogen through electrochemical charging; diffusible hydrogen trapped by dislocations and grain boundaries with a desorption activation energy of 16.9 kJ/mol could rapidly diffuse to crack tip or stress concentration field then reduced the threshold value of stress intensity factor (SIF) of crack growth remarkably, resulting in a decrease of fatigue strength, this portion of hydrogen could diffuse out of sample after atmosphere exposure for 96 h and would have no deleterious effect on fatigue strength; hydrogen trapped by fine, temper-induced (Ti,Mo) precipitates with a desorption activation energy of 17.0 kJ/mol could not diffuse out of sample even atmosphere exposure for 336 h, however could desorb from the trap site under cyclic loading then diffuses to the crack tip or stress concentration field, resulting in a decrease in fatigue strength. Considering the hydrogen content in each hydrogen trapping site the deleterious effect of hydrogen trapped by fine, temper-induced (Ti,Mo) precipitates was relatively small compared to the diffusible hydrogen trapped by dislocations and grain boundaries.