The invention discloses an electric control system and a control method for a railway bridge construction machine. The electric control system comprises a plurality of controllers, a controller area network (CAN) bus, a display for displaying working state indexes of the plurality of controllers in the form of a virtual meter and a remote controller which wirelessly communicates with the plurality of controllers, and is used for controlling the work of the plurality of controllers, wherein the plurality of controllers are connected with the CAN bus in a distributed manner; and the display is connected with the CAN bus. According to the control system, a CAN bus distributed control mode is adopted, so that a large number of control cables and power cables are saved, and the system is convenient to maintain; and furthermore, the display part of the control system adopts a virtual meter, so that a mechanical meter is cancelled, and the space and the resources of a control panel are saved.