The invention relates to a method and a device for installing a typical underwater manifold in a swing mode. The device is characterized by comprising a No.1 installation ship and a No.2 installation ship, wherein the manifold is arranged on a deck of the No.1 installation ship; the top of the manifold is provided with four hydraulic release clamping rings; each hydraulic release clamping ring isconnected with a steel wire rope; the other ends of the four steel wire ropes are connected to the bottom of a triangular plate body with an isosceles triangular vertical section through the hydraulic release clamping rings; the top of the triangular plate body is connected with one corner of a quadrangular plate body with a quadrangular vertical section through the hydraulic release clamping rings; the other corner opposite to the corner is connected with an A-shaped crane on the No.1 installation ship through the hydraulic release clamping rings and cables; the other two corners of the quadrangular plate body are correspondingly with a hydraulic winch on the No.1 installation ship and an A-shaped crane on the No.2 installation ship through the hydraulic release clamping rings and the cables respectively; the No.1 installation ship and the No.2 installation ship are provided with an underwater robot respectively; and the underwater robots are arranged in an umbilical cable managementsystem.