The invention relates to the field of mechanical equipment, in particular a gap-adjustable crossed roller bearing. The gap-adjustable crossed roller bearing comprises a support roller and a horizontal roller; the support roller is installed at the head end of a support axle through a self-aligning bearing; the head end surface of the support axle is provided with a crossed slot; the horizontal roller is installed in the crossed slot through a small shaft; the tail end of the support axle is provided with an eccentric sleeve component for adjusting position of the support axle; the eccentric sleeve component is installed in an installation seat, and the outer end of the eccentric sleeve component is compacted and fixed; and lubricating holes are formed in the support axle to lubricate the self-aligning bearing and the horizontal roller respectively. Through the invention, the eccentric sleeve is rotated to adjust the gap between the support roller and a matching rail, and the direction of the horizontal roller is not changed; the thickness of a gasket is adjusted to adjust the gap between the horizontal roller and a matching rail; the support roller and the horizontal roller are lubricated respectively, and the lubricating oil quantity can be independently adjusted; and the whole crossed roller bearing has simple structure and is easy to adjust.