A shield machine

The invention provides a shield machine capable of strengthening a rotational driving force of a cutter head without using a large and high-capacity electric motor, and capable of making room at and around an axial part for reasonably arranging machinery. A shield machine 1 having a front shell body 2 which is connected to an exchangeable temporary rear shell body at a time of launching from a pit to an anterior ground and is connected to a regular rear shell body 4 as a replacement part of the temporary rear shell body at a time of further excavating the anterior ground after the launch, the front shell body having a rotational shaft 9 rotating a cutter head 6, the temporary rear shell body having a hydraulic motor for driving the rotational shaft, and the regular rear shell body having an electric motor 27 for driving the rotational shaft, the shield machine includes a rotary transmission shaft 31 which is provided with the regular rear shell body and is directly connected, in series, with the rotational sh