This disclosure belongs to the field of organic silicon polymer material preparation, particularly relating to a continuous production device for organophosphorus nitrile-catalyzed high-molecular-weight polysiloxane. It includes a reaction device with a horizontal configuration and dual-axis stirring, where the diameters of the dual axes decrease gradually from the feed port to the discharge outlet, and the corresponding nominal diameters of the paddles increase gradually from the feed port to the discharge outlet. The stirring shaft and paddles are hollow and can be externally heated or cooled. The dual-axis engagement provides mass transfer, heat transfer, and axial propelling force. This reaction device exhibits excellent mass transfer and heat transfer effects, resulting in uniform products with narrow molecular weight distribution and low volatile content. It is particularly suitable for the continuous production of high-viscosity, high-molecular-weight polysiloxanes catalyzed by organophosphorus nitrile. This production device can be adapted to various traditional chemical reaction equipment.