This paper presents an in-depth study on the creep-fatigue damage of deep-sea vehicle pressure hulls in the marine environment using ABAQUS. By constructing geometric models and material constitutive relations, and utilizing the USDFLD subroutine to calculate fatigue and creep damage, the research results show that the pressure hull structure of deep-sea vehicles suffers from both fatigue and creep damage during operation, and the two collaboratively accelerate the degradation and failure of the structure. Taking the operating depth of 1000 m as an example, the effects of different pressures and holding times on creep-fatigue damage are considered respectively, indicating that comprehensively considering fatigue and creep is crucial for accurately predicting the life of pressure hulls. The research in this paper can help predict design defects or weak points of fatigue failure in pressure hulls, thus optimizing the design and improving the service life and safety of pressure hulls.