The linear roller bearing comprises: a pair of ways with their raceway grooves facing each other; a cage disposed between the ways; cylindrical rollers held in the cage between the ways; a rack installed in a cutter escape groove formed in each raceway groove of the way; and a pinion in mesh with the rack and supported in the cage. The meshing between the rack and pinion of the linear roller bearing eliminates the possibility of the cage coming off the ways, thus allowing the ways to be controlled to move reliably and smoothly relative to each other.