Hospital bed comprising: - a frame provided with side members and cross members and having a head end and a foot end opposite each other; - a device for adjusting the height of the frame relative to the ground, this device comprising a head linkage, mounted on the frame at the head end, and a foot linkage, mounted on the frame at the foot end, each linkage (12, 13) comprising a leg and a connecting rod which are articulated with respect to each other and with respect to the frame, each linkage (12, 13) having a folded position, in which the leg juxtaposes the frame, and a deployed position, in which the leg is spaced apart from the frame; - a front chassis comprising at least one roller which is mounted rotatably with respect to the leg of the head linkage, at a lower end thereof, exclusively about a transverse axle; - a rear chassis comprising a foot carriage which is articulated with respect to the leg of the foot linkage at a lower end thereof, and at least one rear loose wheel mounted freely in rotation on the foot carriage; this bed having a lowered position, in which the linkages (12, 13) are folded, and a raised position, in which the linkages (12, 13) are deployed and each roller is in contact with the ground, this bed being characterized in that: - the front chassis comprises a head carriage which is articulated with respect to the leg of the head linkage about a transverse pivot and on which the roller is mounted, and at least one front loose wheel mounted rotatably on the head carriage about a rolling axle and a yaw axle, the head carriage carrying a limit stop designed to interact with the leg of the head linkage, - the bed has a raised position in which the linkages (12, 13) are deployed to the end of their travel and in which, by interaction with the limit stop, the leg of the head linkage places the head carriage in a tilted position in which the roller is spaced apart from the ground and in which the yaw axle of the front wheel is substantially perpendicular to the ground. - a frame provided with side members and cross members and having a head end and a foot end opposite each other; - a device for adjusting the height of the frame relative to the ground, this device comprising a head linkage, mounted on the frame at the head end, and a foot linkage, mounted on the frame at the foot end, each linkage (12, 13) comprising a leg and a connecting rod which are articulated with respect to each other and with respect to the frame, each linkage (12, 13) having a folded position, in which the leg juxtaposes the frame, and a deployed position, in which the leg is spaced apart from the frame; - a front chassis comprising at least one roller which is mounted rotatably with respect to the leg of the head linkage, at a lower end thereof, exclusively about a transverse axle; - a rear chassis comprising a foot carriage which is articulated with respect to the leg of the foot linkage at a lower end thereof, and at least one rear loose wheel mounted freely in rotation on the foot carriage; - the front chassis comprises a head carriage which is articulated with respect to the leg of the head linkage about a transverse pivot and on which the roller is mounted, and at least one front loose wheel mounted rotatably on the head carriage about a rolling axle and a yaw axle, the head carriage carrying a limit stop designed to interact with the leg of the head linkage, - the bed has a raised position in which the linkages (12, 13) are deployed to the end of their travel and in which, by interaction with the limit stop, the leg of the head linkage places the head carriage in a tilted position in which the roller is spaced apart from the ground and in which the yaw axle of the front wheel is substantially perpendicular to the ground.