To provide a bearing device having an excellent lubricity in the bearing device having a roll neck bearing used for the rolling mill of a steel-making facility.

Two (more than two is acceptable) spiral grooves 12Aa and 12Ab and spiral grooves 12Ba and 12Bb are formed in the inner peripheral surfaces of inner rings 12A and 12B. Even when one of the two spiral grooves is clogged, lubrication can be performed by the remaining spiral groove, and the premature wear and abnormal heating of a fitting part can be suppressed over a long period. Also, by forming two or more spiral grooves 12Aa and 12Ab and the spiral grooves 12Ba and 12Bb, the overall length of each spiral groove can be suppressed. As a result, through the holding amount of lubricant is increased, times for the lubricant to reach the ends of the spiral grooves 12Aa and 12Ab and the spiral grooves 12Ba and 12Bb therethrough can be shortened.