A spherical roller bearing has an outer ring with a diameter of at least 499 mm, an inner ring and two sets of spherical rollers accommodated in separate bearing cages. Each bearing cage includes first and second cage rings extending in a circumferential direction of the bearing and a plurality of cage bars extending in an axial direction of the bearing between the first and second cage rings such that closed pockets are formed for receiving the rollers. Each cage bar separates two adjacent pockets and has a first circumferential side face facing a first pocket and a second circumferential side face facing a second pocket, each circumferential side face being provided in the axial direction with a first contact area and second contact area each configured to contact the roller, at least one of the first and second contact areas has a convex curvature in a radial direction.