The effect of hydrogen on contact stresses in a roller bearing fitted with interference on a shaft is investigated. The hydrogen-induced damage to the material of the inner bearing ring is described by the introduction of a weakened layer. It is found out that hydrogen released from the lubricant causes additional expansion of the ring, which reduces the working radial clearance in the bearing and redistributes the axial load between the rolling elements, in some cases increasing the clamping force to the most loaded rolling element. The problem of contact between a cylindrical roller and a bearing ring is solved in terns of the elastic half-space problem. Dimensionless expressions for the stress tensor components in the ring under the contact surface are obtained and the distribution by depth is investigated. It is shown that the equivalent stresses reach maximum at a certain depth. Based on the constructed graphs, a simple method for calculating these values and the depth of their location is proposed. It is shown that with an increase in the pressing force, the dangerous region of high stresses shifts deep into the ring and facilitate the initiation of fatigue subsurface defects.