The utility model discloses a dual-function switching device for rotating-movable arm swinging of a hydraulic excavator, comprising a movable arm swing oil cylinder, a rotary motor, a switching valve, an operating handle, a flow rate distributing valve, a main pump and an oil tank. The dual-functional switching device is characterized in that an inlet of the switching valve is communicated with the flow rate distributing valve; an outlet of the switching valve is respectively communicated with the movable arm swing oil cylinder and the rotary motor; the switching valve is an electric control two-position six-way valve; and the operating handle is a hydraulic pilot control valve of a charged button. When the rotating of the hydraulic excavator is needed, the operating handle leads the switching valve to be in the rotating functional position, and the hydraulic oil flows to the rotary motor to realize rotating; when the swinging of the movable arm is needed, the operating handle leads the switching valve to be in the movable arm swing functional position, and the hydraulic oil flows to the movable arm swing oil cylinder to realize the movable arm swinging. The utility model has the advantages of simple structure, convenient operation, reliable performance, high performance-price ratio and small required space.