Abstract: The present invention relates to an all-dry submersible motor pump with a concordant seal system. In this submersible pump, there is a motor within a motor room, a vertical rotary shaft driven by the motor and connected to a pump. An air chamber is positioned between the motor room and the water pump. An airtight disc is provided between the motor room and the air chamber with a central hole for passing through the vertical rotary shaft. A concordant seal is arranged below the disc and around the central hole. The concordant seal comprises a fluid-seal and a pressure equalizer. The pressure equalizer employs a moist-isolating air envelope for equalizing the pressures on both sides of the disc, cooperates with the shaft fluid-seal to prevent the moist air from invading the motor room and thereby ensure a dry working condition for the windings of the motor.