A cab stopper device 32 is provided between a bracket 23 on a machine frame of a work machine and a cab 25. The cab stopper device 32 restricts relative movement of the cab 25 with respect to the machine frame in the vertical direction. Two through holes 43, 44 are formed in a floor plate 27 of the cab 25. A stopper 48 of the cab stopper device 32 is inserted in the through holes 43, 44 from above. An engaging portion 48a is formed at the lower end of the stopper 48 that projects from the through holes 43, 44 downward of the floor plate 27. The engaging portion 48a is arranged to be engageable with a restricting groove 42 formed in the bracket 23. In this state, a securing portion 48b at the upper end of the stopper 48 is secured to the floor plate 27.