Mechanical arm structure and surgical robot

The invention discloses a mechanical arm structure and a surgical robot, and the mechanical arm structure comprises a fixed seat, a movable seat, a driving mechanism and a driving mechanism, the folding assembly comprises a plurality of arm ends which are mutually and rotatably connected in a matched mode, and the free end of a first arm is rotatably connected with the fixing base; the slave mechanical arm is rotationally mounted at the tail end of the last arm of the folding assembly; when the first arm rotates, other arms are driven to move synchronously to complete folding, and the posture of the slave mechanical arm is kept unchanged all the time. A balance structure used for keeping rotation balance is arranged at the joint of the free end of the first arm and the fixing base. According to the folding mechanism, by designing the folding assembly in synchronous transmission, linear adjustment of the mechanical arm is converted into folding motion, and the weight and the size are greatly reduced under the