A bearing lubricating device, reducing the manufacturing cost and facilitating the dimensional control and the assembly process, comprises a casing provided around an outer ring rotating relatively to a support shaft; and a lubricating member provided in the casing, which is, after the casing has been fitted over the outer periphery of the outer ring, in contact with the outer ring to apply a lubricant contained in the lubricating member to the outer periphery of the outer ring. When the casing is fitted around the outer ring, the lubricating member is in contact with the outer ring in a position either on a line, that extends in parallel to a tangent passing through a contact point between the outer ring and a supported item borne on the outer ring and passes through the center of the outer ring, or on the opposite side of the line to the contact point.