Provided is an artificial muscle device, including a plurality of heat transfer modules including a thermal conductive body in which a plurality of tunnels parallel to each other and a thermoelectric element contacting an outer surface of the thermal conductive body, a connection member connecting a first heat transfer module to a second heat transfer module, the connection member being folded or unfolded according to a distance between the first heat transfer module and the second heat transfer module, a thermal reaction driving member passing through each of the tunnels, the thermal reaction driving member being stretched or contracted in a longitudinal direction of the tunnel according to a temperature of the thermal reaction driving member, and a power transmission part connected to an end of the thermal reaction driving member.