The invention discloses an artificial muscle driving and structural decoupling robot joint, and belongs to the technical field of robot parts. The robot joint comprises a base, a front vertical plate set, a middle vertical plate set and a rear vertical plate. A main joint pulley block is arranged on the front vertical plate set. A first auxiliary joint pulley block and a second auxiliary joint pulley block are arranged on the middle vertical plate set. One end of a first muscle group traction wire is arranged on the main joint pulley block, and the other end of the first muscle group traction wire is arranged on the first auxiliary joint pulley block. One end of a second muscle group traction wire is arranged on the main joint pulley block, and the other end of the second muscle group traction wire is arranged on the second auxiliary joint pulley block. The end of a main joint shaft of the main joint pulley block is connected with a main joint movement arm. Experiments are conducted by means of different artificial muscle actuator units, an auxiliary joint driving pulley block connected with the robot joint is driven by controlling the on and off of currents of all SMA springs in an SMA spring set according to the electro-thermal driving characteristics of the SMA springs, then a main joint driving pulley block is driven to rotate by a certain degree, joint control is achieved, and the interference problem between all the SMA springs is avoided.