Abstract: A ladder climber's safety device for use with stationary ladders of the type having side rails of rectangular cross-sectional configuration includes hand grip members slidable along each rail and loosely interconnected by a cable removably attachable to the safety belt of the climber. The handle grip members include opposed gripping teeth adapted to engage their respective ladder rails when rotated downwardly towards the front of the ladder for preventing free downward movement thereof, and roller wheels adapted to engage the rail edges when the handle grip members are pushed in the upward direction to permit free movement thereof along the rails as controlled by the climber in climbing or descending the ladder.