Improvements in the rolling contact fatigue resistance of bearing steels need to be made, and various researches to achieve this have been implemented. It is particularly important that, among the non-metallic inclusions, the quantity of large-size oxide inclusions be reduced. Therefore, studies looking at minimizing oxide inclusions have been carried out. More recently, however, a new approach to improving the rolling contact fatigue resistance, different from previous methods, has been undertaken. It has been reported that the condition of the contact at the interfaces between the matrix and non-metallic inclusions is important because it affects the stress state around the inclusions, and that this condition needs to be considered to improve the fatigue resistance of bearing steel. In this paper, to develop bearing steel with a rolling fatigue life better than is currently the case, the relationship between the rolling contact fatigue resistance and the composition of oxide inclusions is investigated. By controlling the composition of the oxide inclusions, fatigue failure was avoided in a thrust-type rolling contact fatigue test, and the fatigue life (L₁₀) achieved was greater than 200 million revolutions. The reason for this improvement is considered to be the absence of voids at the interface between the matrix and the non-metallic inclusions, which would otherwise have a negative effect on the fatigue life.