The invention discloses a control network connecting mode of a drag-suction dredger power positioning control system. The system comprises a control computer, a switch, a bow programmable logic controller (PLC), a power positioning PLC, a dredging PLC, a multi-serial-port communication card, a program field bus (PROFIBUS) communication card, an electric gyrocompass, a differential global positioning system (DGPS), an aerovane, a motion unit, a log, a sounding instrument and a dredging track display system. The power positioning PLC is connected with the bow PLC and the dredging PLC through the network switch, and each PLC has a unique internet protocol (IP) address; the electric gyrocompass, the DGPS, the aerovane, the motion unit, the log and the sounding instrument are connected with the control computer through the multi-serial-port communication card; the PLCs are connected with the control computer through the PROFIBUS communication card; the control computer is connected with the dredging track display system through the network switch; and the PLCs and the control computer realize one-to-one communication by adopting data processing (DP) protocols, so that the control requirement of the dredger power positioning control system is met.