A chain block comprising: a first frame rotatably supporting a load sheave member around which a load chain is wound and rotatably supporting a drive shaft which is rotated separately from the load sheave member; a second frame arranged to be opposed to the first frame and cooperating with the first frame to rotatably support the load sheave member and rotatably support the drive shaft; a wheel cover side structure including a hand wheel around which a hand chain is wound and a wheel cover which covers the hand wheel and residing on an opposite side of the first frame in a direction away from the second frame; and a gear case side structure including a plurality of gear members adapted to transmit a rotation force from the hand wheel via the drive shaft to the load sheave member and a gear case covering the gear member and residing on an opposite side of the second frame in a direction away from the first frame, characterized in that, each of the first frame and the second frame is provided with a rolling restriction portion restricting rolling along outer circumferences of the first frame and the second frame in a case of a standing posture in which the first frame and the second frame contact an installation part at the same time, the rolling restriction portion is configured to contact the installation part at a position spaced as much as a predetermined rolling prevention distance from an outer rim portion of each of the first frame and the second frame at the same time as the outer rim portion, the first frame is attached with the gear case in a state of projecting further to an outer circumferential side than the gear case, and the first frame includes a circular portion having an arc-like outer rim portion and a frame projection portion (111a, 111b) projecting to an outer circumferential side from the circular portion and serving as the rolling restriction portion. a first frame rotatably supporting a load sheave member around which a load chain is wound and rotatably supporting a drive shaft which is rotated separately from the load sheave member; a second frame arranged to be opposed to the first frame and cooperating with the first frame to rotatably support the load sheave member and rotatably support the drive shaft; a wheel cover side structure including a hand wheel around which a hand chain is wound and a wheel cover which covers the hand wheel and residing on an opposite side of the first frame in a direction away from the second frame; and a gear case side structure including a plurality of gear members adapted to transmit a rotation force from the hand wheel via the drive shaft to the load sheave member and a gear case covering the gear member and residing on an opposite side of the second frame in a direction away from the first frame, characterized in that, each of the first frame and the second frame is provided with a rolling restriction portion restricting rolling along outer circumferences of the first frame and the second frame in a case of a standing posture in which the first frame and the second frame contact an installation part at the same time, the rolling restriction portion is configured to contact the installation part at a position spaced as much as a predetermined rolling prevention distance from an outer rim portion of each of the first frame and the second frame at the same time as the outer rim portion, the first frame is attached with the gear case in a state of projecting further to an outer circumferential side than the gear case, and the first frame includes a circular portion having an arc-like outer rim portion and a frame projection portion (111a, 111b) projecting to an outer circumferential side from the circular portion and serving as the rolling restriction portion.