A model is suggested which allows one to describe the influence of hydrogen on the stresses in structural materials. The two-dimensional problem of plane elasticity was solved on example of a hollow pipe under internal pressure. Analysis of the stress distribution in the pipe suggests that the radial stress is not considerably affected by hydrogen since the radial stresses are compressive whereas the hydrogen moves to the domains of tensile stresses. The effect of the hydrogen on the hoop stress is essential, namely, the effect of the hydrogen presence (difference between the stresses in the hydrogen-affected material and virgin material) is comparable with and even exceeds the original hoop stress. This effect is especially considerable in the neighborhood of loading. This effect often encounters during the exploitation of gas and oil pipelines since the transported medium is full of hydrogen. The hoop stress is tensile which results in essential influence of the hydrogen on the stress field. Despite the fac