Abstract: A hand brake includes a mounting frame mounted on a handlebar grip of a wheeled walker and defining a working space with an open side and a closed end wall. A cable pull block is disposed inside the working space, and has an upper part pivoted to the mounting frame by a first pivot, and a lower part serving as a force bearing part and connected to a transmission cable under tension. A control lever has a pivot part extending into the working space via the open side thereof, and an operating part extending outwardly of the working space. The pivot part has an upper portion that is provided with an upwardly opening accommodating space. The accommodating space has a base wall. The cable pull block extends downwardly into the accommodating space such that the lower part confronts the base wall. The lower part of the control lever is pivoted to the cable pull block by a second pivot parallel to and disposed below the first pivot.